#line 1 "B/Deparse.pm"
# B::Deparse.pm
# Copyright (c) 1998-2000, 2002, 2003, 2004, 2005, 2006 Stephen McCamant.
# All rights reserved.
# This module is free software; you can redistribute and/or modify
# it under the same terms as Perl itself.

# This is based on the module of the same name by Malcolm Beattie,
# but essentially none of his code remains.

package B::Deparse;
use Carp;
use B qw(class main_root main_start main_cv svref_2object opnumber perlstring
	 OPf_WANT OPf_WANT_VOID OPf_WANT_SCALAR OPf_WANT_LIST
	 OPf_KIDS OPf_REF OPf_STACKED OPf_SPECIAL OPf_MOD OPf_PARENS
	 OPpLVAL_INTRO OPpOUR_INTRO OPpENTERSUB_AMPER OPpSLICE OPpCONST_BARE
	 OPpTRANS_SQUASH OPpTRANS_DELETE OPpTRANS_COMPLEMENT OPpTARGET_MY
	 OPpEXISTS_SUB OPpSORT_NUMERIC OPpSORT_INTEGER OPpREPEAT_DOLIST
	 OPpSORT_REVERSE OPpMULTIDEREF_EXISTS OPpMULTIDEREF_DELETE
	 SVf_IOK SVf_NOK SVf_ROK SVf_POK SVpad_OUR SVf_FAKE SVs_RMG SVs_SMG
	 SVs_PADTMP SVpad_TYPED
         CVf_METHOD CVf_LVALUE
	 PMf_KEEP PMf_GLOBAL PMf_CONTINUE PMf_EVAL PMf_ONCE
	 PMf_MULTILINE PMf_SINGLELINE PMf_FOLD PMf_EXTENDED PMf_EXTENDED_MORE
	 PADNAMEt_OUTER
        MDEREF_reload
        MDEREF_AV_pop_rv2av_aelem
        MDEREF_AV_gvsv_vivify_rv2av_aelem
        MDEREF_AV_padsv_vivify_rv2av_aelem
        MDEREF_AV_vivify_rv2av_aelem
        MDEREF_AV_padav_aelem
        MDEREF_AV_gvav_aelem
        MDEREF_HV_pop_rv2hv_helem
        MDEREF_HV_gvsv_vivify_rv2hv_helem
        MDEREF_HV_padsv_vivify_rv2hv_helem
        MDEREF_HV_vivify_rv2hv_helem
        MDEREF_HV_padhv_helem
        MDEREF_HV_gvhv_helem
        MDEREF_ACTION_MASK
        MDEREF_INDEX_none
        MDEREF_INDEX_const
        MDEREF_INDEX_padsv
        MDEREF_INDEX_gvsv
        MDEREF_INDEX_MASK
        MDEREF_FLAG_last
        MDEREF_MASK
        MDEREF_SHIFT
    );

$VERSION = '1.37';
use strict;
use vars qw/$AUTOLOAD/;
use warnings ();
require feature;

BEGIN {
    # List version-specific constants here.
    # Easiest way to keep this code portable between version looks to
    # be to fake up a dummy constant that will never actually be true.
    foreach (qw(OPpSORT_INPLACE OPpSORT_DESCEND OPpITER_REVERSED OPpCONST_NOVER
		OPpPAD_STATE PMf_SKIPWHITE RXf_SKIPWHITE
		PMf_CHARSET PMf_KEEPCOPY PMf_NOCAPTURE CVf_ANONCONST
		CVf_LOCKED OPpREVERSE_INPLACE OPpSUBSTR_REPL_FIRST
		PMf_NONDESTRUCT OPpCONST_ARYBASE OPpEVAL_BYTES
		OPpLVREF_TYPE OPpLVREF_SV OPpLVREF_AV OPpLVREF_HV
		OPpLVREF_CV OPpLVREF_ELEM SVpad_STATE)) {
	eval { B->import($_) };
	no strict 'refs';
	*{$_} = sub () {0} unless *{$_}{CODE};
    }
}

# Changes between 0.50 and 0.51:
# - fixed nulled leave with live enter in sort { }
# - fixed reference constants (\"str")
# - handle empty programs gracefully
# - handle infinite loops (for (;;) {}, while (1) {})
# - differentiate between 'for my $x ...' and 'my $x; for $x ...'
# - various minor cleanups
# - moved globals into an object
# - added '-u', like B::C
# - package declarations using cop_stash
# - subs, formats and code sorted by cop_seq
# Changes between 0.51 and 0.52:
# - added pp_threadsv (special variables under USE_5005THREADS)
# - added documentation
# Changes between 0.52 and 0.53:
# - many changes adding precedence contexts and associativity
# - added '-p' and '-s' output style options
# - various other minor fixes
# Changes between 0.53 and 0.54:
# - added support for new 'for (1..100)' optimization,
#   thanks to Gisle Aas
# Changes between 0.54 and 0.55:
# - added support for new qr// construct
# - added support for new pp_regcreset OP
# Changes between 0.55 and 0.56:
# - tested on base/*.t, cmd/*.t, comp/*.t, io/*.t
# - fixed $# on non-lexicals broken in last big rewrite
# - added temporary fix for change in opcode of OP_STRINGIFY
# - fixed problem in 0.54's for() patch in 'for (@ary)'
# - fixed precedence in conditional of ?:
# - tweaked list paren elimination in 'my($x) = @_'
# - made continue-block detection trickier wrt. null ops
# - fixed various prototype problems in pp_entersub
# - added support for sub prototypes that never get GVs
# - added unquoting for special filehandle first arg in truncate
# - print doubled rv2gv (a bug) as '*{*GV}' instead of illegal '**GV'
# - added semicolons at the ends of blocks
# - added -l '#line' declaration option -- fixes cmd/subval.t 27,28
# Changes between 0.56 and 0.561:
# - fixed multiply-declared my var in pp_truncate (thanks to Sarathy)
# - used new B.pm symbolic constants (done by Nick Ing-Simmons)
# Changes between 0.561 and 0.57:
# - stylistic changes to symbolic constant stuff
# - handled scope in s///e replacement code
# - added unquote option for expanding "" into concats, etc.
# - split method and proto parts of pp_entersub into separate functions
# - various minor cleanups
# Changes after 0.57:
# - added parens in \&foo (patch by Albert Dvornik)
# Changes between 0.57 and 0.58:
# - fixed '0' statements that weren't being printed
# - added methods for use from other programs
#   (based on patches from James Duncan and Hugo van der Sanden)
# - added -si and -sT to control indenting (also based on a patch from Hugo)
# - added -sv to print something else instead of '???'
# - preliminary version of utf8 tr/// handling
# Changes after 0.58:
# - uses of $op->ppaddr changed to new $op->name (done by Sarathy)
# - added support for Hugo's new OP_SETSTATE (like nextstate)
# Changes between 0.58 and 0.59
# - added support for Chip's OP_METHOD_NAMED
# - added support for Ilya's OPpTARGET_MY optimization
# - elided arrows before '()' subscripts when possible
# Changes between 0.59 and 0.60
# - support for method attributes was added
# - some warnings fixed
# - separate recognition of constant subs
# - rewrote continue block handling, now recognizing for loops
# - added more control of expanding control structures
# Changes between 0.60 and 0.61 (mostly by Robin Houston)
# - many bug-fixes
# - support for pragmas and 'use'
# - support for the little-used $[ variable
# - support for __DATA__ sections
# - UTF8 support
# - BEGIN, CHECK, INIT and END blocks
# - scoping of subroutine declarations fixed
# - compile-time output from the input program can be suppressed, so that the
#   output is just the deparsed code. (a change to O.pm in fact)
# - our() declarations
# - *all* the known bugs are now listed in the BUGS section
# - comprehensive test mechanism (TEST -deparse)
# Changes between 0.62 and 0.63 (mostly by Rafael Garcia-Suarez)
# - bug-fixes
# - new switch -P
# - support for command-line switches (-l, -0, etc.)
# Changes between 0.63 and 0.64
# - support for //, CHECK blocks, and assertions
# - improved handling of foreach loops and lexicals
# - option to use Data::Dumper for constants
# - more bug fixes
# - discovered lots more bugs not yet fixed
#
# ...
#
# Changes between 0.72 and 0.73
# - support new switch constructs

# Todo:
#  (See also BUGS section at the end of this file)
#
# - finish tr/// changes
# - add option for even more parens (generalize \&foo change)
# - left/right context
# - copy comments (look at real text with $^P?)
# - avoid semis in one-statement blocks
# - associativity of &&=, ||=, ?:
# - ',' => '=>' (auto-unquote?)
# - break long lines ("\r" as discretionary break?)
# - configurable syntax highlighting: ANSI color, HTML, TeX, etc.
# - more style options: brace style, hex vs. octal, quotes, ...
# - print big ints as hex/octal instead of decimal (heuristic?)
# - handle 'my $x if 0'?
# - version using op_next instead of op_first/sibling?
# - avoid string copies (pass arrays, one big join?)
# - here-docs?

# Current test.deparse failures
# comp/hints 6 - location of BEGIN blocks wrt. block openings
# run/switchI 1 - missing -I switches entirely
#    perl -Ifoo -e 'print @INC'
# op/caller 2 - warning mask propagates backwards before warnings::register
#    'use warnings; BEGIN {${^WARNING_BITS} eq "U"x12;} use warnings::register'
# op/getpid 2 - can't assign to shared my() declaration (threads only)
#    'my $x : shared = 5'
# op/override 7 - parens on overridden require change v-string interpretation
#    'BEGIN{*CORE::GLOBAL::require=sub {}} require v5.6'
#    c.f. 'BEGIN { *f = sub {0} }; f 2'
# op/pat 774 - losing Unicode-ness of Latin1-only strings
#    'use charnames ":short"; $x="\N{latin:a with acute}"'
# op/recurse 12 - missing parens on recursive call makes it look like method
#    'sub f { f($x) }'
# op/subst 90 - inconsistent handling of utf8 under "use utf8"
# op/taint 29 - "use re 'taint'" deparsed in the wrong place wrt. block open
# op/tiehandle compile - "use strict" deparsed in the wrong place
# uni/tr_ several
# ext/B/t/xref 11 - line numbers when we add newlines to one-line subs
# ext/Data/Dumper/t/dumper compile
# ext/DB_file/several
# ext/Encode/several
# ext/Ernno/Errno warnings
# ext/IO/lib/IO/t/io_sel 23
# ext/PerlIO/t/encoding compile
# ext/POSIX/t/posix 6
# ext/Socket/Socket 8
# ext/Storable/t/croak compile
# lib/Attribute/Handlers/t/multi compile
# lib/bignum/ several
# lib/charnames 35
# lib/constant 32
# lib/English 40
# lib/ExtUtils/t/bytes 4
# lib/File/DosGlob compile
# lib/Filter/Simple/t/data 1
# lib/Math/BigInt/t/constant 1
# lib/Net/t/config Deparse-warning
# lib/overload compile
# lib/Switch/ several
# lib/Symbol 4
# lib/Test/Simple several
# lib/Term/Complete
# lib/Tie/File/t/29_downcopy 5
# lib/vars 22

# Object fields:
#
# in_coderef2text:
# True when deparsing via $deparse->coderef2text; false when deparsing the
# main program.
#
# avoid_local:
# (local($a), local($b)) and local($a, $b) have the same internal
# representation but the short form looks better. We notice we can
# use a large-scale local when checking the list, but need to prevent
# individual locals too. This hash holds the addresses of OPs that
# have already had their local-ness accounted for. The same thing
# is done with my().
#
# curcv:
# CV for current sub (or main program) being deparsed
#
# curcvlex:
# Cached hash of lexical variables for curcv: keys are
# names prefixed with "m" or "o" (representing my/our), and
# each value is an array with two elements indicating the cop_seq
# of scopes in which a var of that name is valid and a third ele-
# ment referencing the pad name.
#
# curcop:
# COP for statement being deparsed
#
# curstash:
# name of the current package for deparsed code
#
# subs_todo:
# array of [cop_seq, CV, is_format?, name] for subs and formats we still
# want to deparse.  The fourth element is a pad name thingy for lexical
# subs or a string for special blocks.  For other subs, it is undef.  For
# lexical subs, CV may be undef, indicating a stub declaration.
#
# protos_todo:
# as above, but [name, prototype] for subs that never got a GV
#
# subs_done, forms_done:
# keys are addresses of GVs for subs and formats we've already
# deparsed (or at least put into subs_todo)
#
# subs_declared
# keys are names of subs for which we've printed declarations.
# That means we can omit parentheses from the arguments. It also means we
# need to put CORE:: on core functions of the same name.
#
# in_subst_repl
# True when deparsing the replacement part of a substitution.
#
# in_refgen
# True when deparsing the argument to \.
#
# parens: -p
# linenums: -l
# unquote: -q
# cuddle: ' ' or '\n', depending on -sC
# indent_size: -si
# use_tabs: -sT
# ex_const: -sv

# A little explanation of how precedence contexts and associativity
# work:
#
# deparse() calls each per-op subroutine with an argument $cx (short
# for context, but not the same as the cx* in the perl core), which is
# a number describing the op's parents in terms of precedence, whether
# they're inside an expression or at statement level, etc.  (see
# chart below). When ops with children call deparse on them, they pass
# along their precedence. Fractional values are used to implement
# associativity ('($x + $y) + $z' => '$x + $y + $y') and related
# parentheses hacks. The major disadvantage of this scheme is that
# it doesn't know about right sides and left sides, so say if you
# assign a listop to a variable, it can't tell it's allowed to leave
# the parens off the listop.

# Precedences:
# 26             [TODO] inside interpolation context ("")
# 25 left        terms and list operators (leftward)
# 24 left        ->
# 23 nonassoc    ++ --
# 22 right       **
# 21 right       ! ~ \ and unary + and -
# 20 left        =~ !~
# 19 left        * / % x
# 18 left        + - .
# 17 left        << >>
# 16 nonassoc    named unary operators
# 15 nonassoc    < > <= >= lt gt le ge
# 14 nonassoc    == != <=> eq ne cmp
# 13 left        &
# 12 left        | ^
# 11 left        &&
# 10 left        ||
#  9 nonassoc    ..  ...
#  8 right       ?:
#  7 right       = += -= *= etc.
#  6 left        , =>
#  5 nonassoc    list operators (rightward)
#  4 right       not
#  3 left        and
#  2 left        or xor
#  1             statement modifiers
#  0.5           statements, but still print scopes as do { ... }
#  0             statement level
# -1             format body

# Nonprinting characters with special meaning:
# \cS - steal parens (see maybe_parens_unop)
# \n - newline and indent
# \t - increase indent
# \b - decrease indent ('outdent')
# \f - flush left (no indent)
# \cK - kill following semicolon, if any

# Semicolon handling:
#  - Individual statements are not deparsed with trailing semicolons.
#    (If necessary, \cK is tacked on to the end.)
#  - Whatever code joins statements together or emits them (lineseq,
#    scopeop, deparse_root) is responsible for adding semicolons where
#    necessary.
#  - use statements are deparsed with trailing semicolons because they are
#    immediately concatenated with the following statement.
#  - indent() removes semicolons wherever it sees \cK.


BEGIN { for (qw[ const stringify rv2sv list glob pushmark null aelem
		 nextstate dbstate rv2av rv2hv helem custom ]) {
    eval "sub OP_\U$_ () { " . opnumber($_) . "}"
}}

# _pessimise_walk(): recursively walk the optree of a sub,
# possibly undoing optimisations along the way.

sub _pessimise_walk {
    my ($self, $startop) = @_;

    return unless $$startop;
    my ($op, $prevop);
    for ($op = $startop; $$op; $prevop = $op, $op = $op->sibling) {
	my $ppname = $op->name;

	# pessimisations start here

	if ($ppname eq "padrange") {
	    # remove PADRANGE:
	    # the original optimisation either (1) changed this:
	    #    pushmark -> (various pad and list and null ops) -> the_rest
	    # or (2), for the = @_ case, changed this:
	    #    pushmark -> gv[_] -> rv2av -> (pad stuff)       -> the_rest
	    # into this:
	    #    padrange ----------------------------------------> the_rest
	    # so we just need to convert the padrange back into a
	    # pushmark, and in case (1), set its op_next to op_sibling,
	    # which is the head of the original chain of optimised-away
	    # pad ops, or for (2), set it to sibling->first, which is
	    # the original gv[_].

	    $B::overlay->{$$op} = {
		    type => OP_PUSHMARK,
		    name => 'pushmark',
		    private => ($op->private & OPpLVAL_INTRO),
	    };
	}

	# pessimisations end here

	if (class($op) eq 'PMOP'
	    && ref($op->pmreplroot)
	    && ${$op->pmreplroot}
	    && $op->pmreplroot->isa( 'B::OP' ))
	{
	    $self-> _pessimise_walk($op->pmreplroot);
	}

	if ($op->flags & OPf_KIDS) {
	    $self-> _pessimise_walk($op->first);
	}

    }
}


# _pessimise_walk_exe(): recursively walk the op_next chain of a sub,
# possibly undoing optimisations along the way.

sub _pessimise_walk_exe {
    my ($self, $startop, $visited) = @_;

    return unless $$startop;
    return if $visited->{$$startop};
    my ($op, $prevop);
    for ($op = $startop; $$op; $prevop = $op, $op = $op->next) {
	last if $visited->{$$op};
	$visited->{$$op} = 1;
	my $ppname = $op->name;
	if ($ppname =~
	    /^((and|d?or)(assign)?|(map|grep)while|range|cond_expr|once)$/
	    # entertry is also a logop, but its op_other invariably points
	    # into the same chain as the main execution path, so we skip it
	) {
	    $self->_pessimise_walk_exe($op->other, $visited);
	}
	elsif ($ppname eq "subst") {
	    $self->_pessimise_walk_exe($op->pmreplstart, $visited);
	}
	elsif ($ppname =~ /^(enter(loop|iter))$/) {
	    # redoop and nextop will already be covered by the main block
	    # of the loop
	    $self->_pessimise_walk_exe($op->lastop, $visited);
	}

	# pessimisations start here
    }
}

# Go through an optree and "remove" some optimisations by using an
# overlay to selectively modify or un-null some ops. Deparsing in the
# absence of those optimisations is then easier.
#
# Note that older optimisations are not removed, as Deparse was already
# written to recognise them before the pessimise/overlay system was added.

sub pessimise {
    my ($self, $root, $start) = @_;

    # walk tree in root-to-branch order
    $self->_pessimise_walk($root);

    my %visited;
    # walk tree in execution order
    $self->_pessimise_walk_exe($start, \%visited);
}


sub null {
    my $op = shift;
    return class($op) eq "NULL";
}

sub todo {
    my $self = shift;
    my($cv, $is_form, $name) = @_;
    my $cvfile = $cv->FILE//'';
    return unless ($cvfile eq $0 || exists $self->{files}{$cvfile});
    my $seq;
    if ($cv->OUTSIDE_SEQ) {
	$seq = $cv->OUTSIDE_SEQ;
    } elsif (!null($cv->START) and is_state($cv->START)) {
	$seq = $cv->START->cop_seq;
    } else {
	$seq = 0;
    }
    push @{$self->{'subs_todo'}}, [$seq, $cv, $is_form, $name];
}

sub next_todo {
    my $self = shift;
    my $ent = shift @{$self->{'subs_todo'}};
    my $cv = $ent->[1];
    if (ref $ent->[3]) { # lexical sub
	my @text;

	# At this point, we may not yet have deparsed the hints that allow
	# lexical subroutines to be recognized.  So adjust the current
	# hints and deparse them.
	# When lex subs cease being experimental, we should be able to
	# remove this code.
	{
	    local $^H = $self->{'hints'};
	    local %^H = %{ $self->{'hinthash'} || {} };
	    local ${^WARNING_BITS} = $self->{'warnings'};
	    feature->import("lexical_subs");
	    warnings->unimport("experimental::lexical_subs");
	    # Here we depend on the fact that individual features
	    # will always set the feature bundle to ‘custom’
	    # (== $feature::hint_mask).  If we had another specific bundle
	    # enabled previously, normalise it.
	    if (($self->{'hints'} & $feature::hint_mask)
		    != $feature::hint_mask)
	    {
		if ($self->{'hinthash'}) {
		    delete $self->{'hinthash'}{$_}
			for grep /^feature_/, keys %{$self->{'hinthash'}};
		}
		else { $self->{'hinthash'} = {} }
		$self->{'hinthash'}
		    = _features_from_bundle(@$self{'hints','hinthash'});
	    }
	    push @text, $self->declare_hinthash($self->{'hinthash'}, \%^H,
						$self->{indent_size}, $^H);
	    push @text, $self->declare_warnings($self->{'warnings'},
						${^WARNING_BITS})
		unless ($self->{'warnings'} // 'u')
		    eq (${^WARNING_BITS   } // 'u');
	    $self->{'warnings'} = ${^WARNING_BITS};
	    $self->{'hints'} = $^H;
	    $self->{'hinthash'} = {%^H};
	}

	# Now emit the sub itself.
	my $padname = $ent->[3];
	my $flags = $padname->FLAGS;
	push @text,
	    !$cv || $ent->[0] <= $padname->COP_SEQ_RANGE_LOW
		? $self->keyword($flags & SVpad_OUR
				    ? "our"
				    : $flags & SVpad_STATE
					? "state"
					: "my") . " "
		: "";
	# XXX We would do $self->keyword("sub"), but ‘my CORE::sub’
	#     doesn’t work and ‘my sub’ ignores a &sub in scope.  I.e.,
	#     we have a core bug here.
	push @text, "sub " . substr $padname->PVX, 1;
	if ($cv) {
	    # my sub foo { }
	    push @text,  " " . $self->deparse_sub($cv);
	    $text[-1] =~ s/ ;$/;/;
	}
	else {
	    # my sub foo;
	    push @text, ";\n";
	}
	return join "", @text;
    }
    my $gv = $cv->GV;
    my $name = $ent->[3] // $self->gv_name($gv);
    if ($ent->[2]) {
	return $self->keyword("format") . " $name =\n"
	    . $self->deparse_format($ent->[1]). "\n";
    } else {
	my $use_dec;
	if ($name eq "BEGIN") {
	    $use_dec = $self->begin_is_use($cv);
	    if (defined ($use_dec) and $self->{'expand'} < 5) {
		return () if 0 == length($use_dec);
		$use_dec =~ s/^(use|no)\b/$self->keyword($1)/e;
	    }
	}
	my $l = '';
	if ($self->{'linenums'}) {
	    my $line = $gv->LINE;
	    my $file = $gv->FILE;
	    $l = "\n\f#line $line \"$file\"\n";
	}
	my $p = '';
	my $stash;
	if (class($cv->STASH) ne "SPECIAL") {
	    $stash = $cv->STASH->NAME;
	    if ($stash ne $self->{'curstash'}) {
		$p = $self->keyword("package") . " $stash;\n";
		$name = "$self->{'curstash'}::$name" unless $name =~ /::/;
		$self->{'curstash'} = $stash;
	    }
	}
	if ($use_dec) {
	    return "$p$l$use_dec";
	}
        if ( $name !~ /::/ and $self->lex_in_scope("&$name")
                            || $self->lex_in_scope("&$name", 1) )
        {
            $name = "$self->{'curstash'}::$name";
        } elsif (defined $stash) {
            $name =~ s/^\Q$stash\E::(?!\z|.*::)//;
        }
	my $ret = "${p}${l}" . $self->keyword("sub") . " $name "
	      . $self->deparse_sub($cv);
	$self->{'subs_declared'}{$name} = 1;
	return $ret;
    }
}

# Return a "use" declaration for this BEGIN block, if appropriate
sub begin_is_use {
    my ($self, $cv) = @_;
    my $root = $cv->ROOT;
    local @$self{qw'curcv curcvlex'} = ($cv);
    local $B::overlay = {};
    $self->pessimise($root, $cv->START);
#require B::Debug;
#B::walkoptree($cv->ROOT, "debug");
    my $lineseq = $root->first;
    return if $lineseq->name ne "lineseq";

    my $req_op = $lineseq->first->sibling;
    return if $req_op->name ne "require";

    my $module;
    if ($req_op->first->private & OPpCONST_BARE) {
	# Actually it should always be a bareword
	$module = $self->const_sv($req_op->first)->PV;
	$module =~ s[/][::]g;
	$module =~ s/.pm$//;
    }
    else {
	$module = $self->const($self->const_sv($req_op->first), 6);
    }

    my $version;
    my $version_op = $req_op->sibling;
    return if class($version_op) eq "NULL";
    if ($version_op->name eq "lineseq") {
	# We have a version parameter; skip nextstate & pushmark
	my $constop = $version_op->first->next->next;

	return unless $self->const_sv($constop)->PV eq $module;
	$constop = $constop->sibling;
	$version = $self->const_sv($constop);
	if (class($version) eq "IV") {
	    $version = $version->int_value;
	} elsif (class($version) eq "NV") {
	    $version = $version->NV;
	} elsif (class($version) ne "PVMG") {
	    # Includes PVIV and PVNV
	    $version = $version->PV;
	} else {
	    # version specified as a v-string
	    $version = 'v'.join '.', map ord, split //, $version->PV;
	}
	$constop = $constop->sibling;
	return if $constop->name ne "method_named";
	return if $self->meth_sv($constop)->PV ne "VERSION";
    }

    $lineseq = $version_op->sibling;
    return if $lineseq->name ne "lineseq";
    my $entersub = $lineseq->first->sibling;
    if ($entersub->name eq "stub") {
	return "use $module $version ();\n" if defined $version;
	return "use $module ();\n";
    }
    return if $entersub->name ne "entersub";

    # See if there are import arguments
    my $args = '';

    my $svop = $entersub->first->sibling; # Skip over pushmark
    return unless $self->const_sv($svop)->PV eq $module;

    # Pull out the arguments
    for ($svop=$svop->sibling; index($svop->name, "method_") != 0;
		$svop = $svop->sibling) {
	$args .= ", " if length($args);
	$args .= $self->deparse($svop, 6);
    }

    my $use = 'use';
    my $method_named = $svop;
    return if $method_named->name ne "method_named";
    my $method_name = $self->meth_sv($method_named)->PV;

    if ($method_name eq "unimport") {
	$use = 'no';
    }

    # Certain pragmas are dealt with using hint bits,
    # so we ignore them here
    if ($module eq 'strict' || $module eq 'integer'
	|| $module eq 'bytes' || $module eq 'warnings'
	|| $module eq 'feature') {
	return "";
    }

    if (defined $version && length $args) {
	return "$use $module $version ($args);\n";
    } elsif (defined $version) {
	return "$use $module $version;\n";
    } elsif (length $args) {
	return "$use $module ($args);\n";
    } else {
	return "$use $module;\n";
    }
}

sub stash_subs {
    my ($self, $pack, $seen) = @_;
    my (@ret, $stash);
    if (!defined $pack) {
	$pack = '';
	$stash = \%::;
    }
    else {
	$pack =~ s/(::)?$/::/;
	no strict 'refs';
	$stash = \%{"main::$pack"};
    }
    return
	if ($seen ||= {})->{
	    $INC{"overload.pm"} ? overload::StrVal($stash) : $stash
	   }++;
    my %stash = svref_2object($stash)->ARRAY;
    while (my ($key, $val) = each %stash) {
	my $flags = $val->FLAGS;
	if ($flags & SVf_ROK) {
	    # A reference.  Dump this if it is a reference to a CV.  If it
	    # is a constant acting as a proxy for a full subroutine, then
	    # we may or may not have to dump it.  If some form of perl-
	    # space visible code must have created it, be it a use
	    # statement, or some direct symbol-table manipulation code that
	    # we will deparse, then we don’t want to dump it.  If it is the
	    # result of a declaration like sub f () { 42 } then we *do*
	    # want to dump it.  The only way to distinguish these seems
	    # to be the SVs_PADTMP flag on the constant, which is admit-
	    # tedly a hack.
	    my $class = class(my $referent = $val->RV);
	    if ($class eq "CV") {
		$self->todo($referent, 0);
	    } elsif (
		$class !~ /^(AV|HV|CV|FM|IO|SPECIAL)\z/
		# A more robust way to write that would be this, but B does
		# not provide the SVt_ constants:
		# ($referent->FLAGS & B::SVTYPEMASK) < B::SVt_PVAV
		and $referent->FLAGS & SVs_PADTMP
	    ) {
		push @{$self->{'protos_todo'}}, [$pack . $key, $val];
	    }
	} elsif ($flags & (SVf_POK|SVf_IOK)) {
	    # Just a prototype. As an ugly but fairly effective way
	    # to find out if it belongs here is to see if the AUTOLOAD
	    # (if any) for the stash was defined in one of our files.
	    my $A = $stash{"AUTOLOAD"};
	    if (defined ($A) && class($A) eq "GV" && defined($A->CV)
		&& class($A->CV) eq "CV") {
		my $AF = $A->FILE;
		next unless $AF eq $0 || exists $self->{'files'}{$AF};
	    }
	    push @{$self->{'protos_todo'}},
		 [$pack . $key, $flags & SVf_POK ? $val->PV: undef];
	} elsif (class($val) eq "GV") {
	    if (class(my $cv = $val->CV) ne "SPECIAL") {
		next if $self->{'subs_done'}{$$val}++;
		next if $$val != ${$cv->GV};   # Ignore imposters
		$self->todo($cv, 0);
	    }
	    if (class(my $cv = $val->FORM) ne "SPECIAL") {
		next if $self->{'forms_done'}{$$val}++;
		next if $$val != ${$cv->GV};   # Ignore imposters
		$self->todo($cv, 1);
	    }
	    if (class($val->HV) ne "SPECIAL" && $key =~ /::$/) {
		$self->stash_subs($pack . $key, $seen);
	    }
	}
    }
}

sub print_protos {
    my $self = shift;
    my $ar;
    my @ret;
    foreach $ar (@{$self->{'protos_todo'}}) {
	my $body = defined $ar->[1]
		? ref $ar->[1]
		    ? " () {\n    " . $self->const($ar->[1]->RV,0) . ";\n}"
		    : " (". $ar->[1] . ");"
		: ";";
	push @ret, "sub " . $ar->[0] .  "$body\n";
    }
    delete $self->{'protos_todo'};
    return @ret;
}

sub style_opts {
    my $self = shift;
    my $opts = shift;
    my $opt;
    while (length($opt = substr($opts, 0, 1))) {
	if ($opt eq "C") {
	    $self->{'cuddle'} = " ";
	    $opts = substr($opts, 1);
	} elsif ($opt eq "i") {
	    $opts =~ s/^i(\d+)//;
	    $self->{'indent_size'} = $1;
	} elsif ($opt eq "T") {
	    $self->{'use_tabs'} = 1;
	    $opts = substr($opts, 1);
	} elsif ($opt eq "v") {
	    $opts =~ s/^v([^.]*)(.|$)//;
	    $self->{'ex_const'} = $1;
	}
    }
}

sub new {
    my $class = shift;
    my $self = bless {}, $class;
    $self->{'cuddle'} = "\n";
    $self->{'curcop'} = undef;
    $self->{'curstash'} = "main";
    $self->{'ex_const'} = "'???'";
    $self->{'expand'} = 0;
    $self->{'files'} = {};
    $self->{'indent_size'} = 4;
    $self->{'linenums'} = 0;
    $self->{'parens'} = 0;
    $self->{'subs_todo'} = [];
    $self->{'unquote'} = 0;
    $self->{'use_dumper'} = 0;
    $self->{'use_tabs'} = 0;

    $self->{'ambient_arybase'} = 0;
    $self->{'ambient_warnings'} = undef; # Assume no lexical warnings
    $self->{'ambient_hints'} = 0;
    $self->{'ambient_hinthash'} = undef;
    $self->init();

    while (my $arg = shift @_) {
	if ($arg eq "-d") {
	    $self->{'use_dumper'} = 1;
	    require Data::Dumper;
	} elsif ($arg =~ /^-f(.*)/) {
	    $self->{'files'}{$1} = 1;
	} elsif ($arg eq "-l") {
	    $self->{'linenums'} = 1;
	} elsif ($arg eq "-p") {
	    $self->{'parens'} = 1;
	} elsif ($arg eq "-P") {
	    $self->{'noproto'} = 1;
	} elsif ($arg eq "-q") {
	    $self->{'unquote'} = 1;
	} elsif (substr($arg, 0, 2) eq "-s") {
	    $self->style_opts(substr $arg, 2);
	} elsif ($arg =~ /^-x(\d)$/) {
	    $self->{'expand'} = $1;
	}
    }
    return $self;
}

{
    # Mask out the bits that L<warnings::register> uses
    my $WARN_MASK;
    BEGIN {
	$WARN_MASK = $warnings::Bits{all} | $warnings::DeadBits{all};
    }
    sub WARN_MASK () {
	return $WARN_MASK;
    }
}

# Initialise the contextual information, either from
# defaults provided with the ambient_pragmas method,
# or from perl's own defaults otherwise.
sub init {
    my $self = shift;

    $self->{'arybase'}  = $self->{'ambient_arybase'};
    $self->{'warnings'} = defined ($self->{'ambient_warnings'})
				? $self->{'ambient_warnings'} & WARN_MASK
				: undef;
    $self->{'hints'}    = $self->{'ambient_hints'};
    $self->{'hints'} &= 0xFF if $] < 5.009;
    $self->{'hinthash'} = $self->{'ambient_hinthash'};

    # also a convenient place to clear out subs_declared
    delete $self->{'subs_declared'};
}

sub compile {
    my(@args) = @_;
    return sub {
	my $self = B::Deparse->new(@args);
	# First deparse command-line args
	if (defined $^I) { # deparse -i
	    print q(BEGIN { $^I = ).perlstring($^I).qq(; }\n);
	}
	if ($^W) { # deparse -w
	    print qq(BEGIN { \$^W = $^W; }\n);
	}
	if ($/ ne "\n" or defined $O::savebackslash) { # deparse -l and -0
	    my $fs = perlstring($/) || 'undef';
	    my $bs = perlstring($O::savebackslash) || 'undef';
	    print qq(BEGIN { \$/ = $fs; \$\\ = $bs; }\n);
	}
	my @BEGINs  = B::begin_av->isa("B::AV") ? B::begin_av->ARRAY : ();
	my @UNITCHECKs = B::unitcheck_av->isa("B::AV")
	    ? B::unitcheck_av->ARRAY
	    : ();
	my @CHECKs  = B::check_av->isa("B::AV") ? B::check_av->ARRAY : ();
	my @INITs   = B::init_av->isa("B::AV") ? B::init_av->ARRAY : ();
	my @ENDs    = B::end_av->isa("B::AV") ? B::end_av->ARRAY : ();
	my @names = qw(BEGIN UNITCHECK CHECK INIT END);
	my @blocks = \(@BEGINs, @UNITCHECKs, @CHECKs, @INITs, @ENDs);
	while (@names) {
	    my ($name, $blocks) = (shift @names, shift @blocks);
	    for my $block (@$blocks) {
		$self->todo($block, 0, $name);
	    }
	}
	$self->stash_subs();
	local($SIG{"__DIE__"}) =
	  sub {
	      if ($self->{'curcop'}) {
		  my $cop = $self->{'curcop'};
		  my($line, $file) = ($cop->line, $cop->file);
		  print STDERR "While deparsing $file near line $line,\n";
	      }
	    };
	$self->{'curcv'} = main_cv;
	$self->{'curcvlex'} = undef;
	print $self->print_protos;
	@{$self->{'subs_todo'}} =
	  sort {$a->[0] <=> $b->[0]} @{$self->{'subs_todo'}};
	my $root = main_root;
	local $B::overlay = {};
	unless (null $root) {
	    $self->pad_subs($self->{'curcv'});
	    # Check for a stub-followed-by-ex-cop, resulting from a program
	    # consisting solely of sub declarations.  For backward-compati-
	    # bility (and sane output) we don’t want to emit the stub.
	    #   leave
	    #     enter
	    #     stub
	    #     ex-nextstate (or ex-dbstate)
	    my $kid;
	    if ( $root->name eq 'leave'
	     and ($kid = $root->first)->name eq 'enter'
	     and !null($kid = $kid->sibling) and $kid->name eq 'stub'
	     and !null($kid = $kid->sibling) and $kid->name eq 'null'
	     and class($kid) eq 'COP' and null $kid->sibling )
	    {
		# ignore
	    } else {
		$self->pessimise($root, main_start);
		print $self->indent($self->deparse_root($root)), "\n";
	    }
	}
	my @text;
	while (scalar(@{$self->{'subs_todo'}})) {
	    push @text, $self->next_todo;
	}
	print $self->indent(join("", @text)), "\n" if @text;

	# Print __DATA__ section, if necessary
	no strict 'refs';
	my $laststash = defined $self->{'curcop'}
	    ? $self->{'curcop'}->stash->NAME : $self->{'curstash'};
	if (defined *{$laststash."::DATA"}{IO}) {
	    print $self->keyword("package") . " $laststash;\n"
		unless $laststash eq $self->{'curstash'};
	    print $self->keyword("__DATA__") . "\n";
	    print readline(*{$laststash."::DATA"});
	}
    }
}

sub coderef2text {
    my $self = shift;
    my $sub = shift;
    croak "Usage: ->coderef2text(CODEREF)" unless UNIVERSAL::isa($sub, "CODE");

    $self->init();
    local $self->{in_coderef2text} = 1;
    return $self->indent($self->deparse_sub(svref_2object($sub)));
}

my %strict_bits = do {
    local $^H;
    map +($_ => strict::bits($_)), qw/refs subs vars/
};

sub ambient_pragmas {
    my $self = shift;
    my ($arybase, $hint_bits, $warning_bits, $hinthash) = (0, 0);

    while (@_ > 1) {
	my $name = shift();
	my $val  = shift();

	if ($name eq 'strict') {
	    require strict;

	    if ($val eq 'none') {
		$hint_bits &= $strict_bits{$_} for qw/refs subs vars/;
		next();
	    }

	    my @names;
	    if ($val eq "all") {
		@names = qw/refs subs vars/;
	    }
	    elsif (ref $val) {
		@names = @$val;
	    }
	    else {
		@names = split' ', $val;
	    }
	    $hint_bits |= $strict_bits{$_} for @names;
	}

	elsif ($name eq '$[') {
	    if (OPpCONST_ARYBASE) {
		$arybase = $val;
	    } else {
		croak "\$[ can't be non-zero on this perl" unless $val == 0;
	    }
	}

	elsif ($name eq 'integer'
	    || $name eq 'bytes'
	    || $name eq 'utf8') {
	    require "$name.pm";
	    if ($val) {
		$hint_bits |= ${$::{"${name}::"}{"hint_bits"}};
	    }
	    else {
		$hint_bits &= ~${$::{"${name}::"}{"hint_bits"}};
	    }
	}

	elsif ($name eq 're') {
	    require re;
	    if ($val eq 'none') {
		$hint_bits &= ~re::bits(qw/taint eval/);
		next();
	    }

	    my @names;
	    if ($val eq 'all') {
		@names = qw/taint eval/;
	    }
	    elsif (ref $val) {
		@names = @$val;
	    }
	    else {
		@names = split' ',$val;
	    }
	    $hint_bits |= re::bits(@names);
	}

	elsif ($name eq 'warnings') {
	    if ($val eq 'none') {
		$warning_bits = $warnings::NONE;
		next();
	    }

	    my @names;
	    if (ref $val) {
		@names = @$val;
	    }
	    else {
		@names = split/\s+/, $val;
	    }

	    $warning_bits = $warnings::NONE if !defined ($warning_bits);
	    $warning_bits |= warnings::bits(@names);
	}

	elsif ($name eq 'warning_bits') {
	    $warning_bits = $val;
	}

	elsif ($name eq 'hint_bits') {
	    $hint_bits = $val;
	}

	elsif ($name eq '%^H') {
	    $hinthash = $val;
	}

	else {
	    croak "Unknown pragma type: $name";
	}
    }
    if (@_) {
	croak "The ambient_pragmas method expects an even number of args";
    }

    $self->{'ambient_arybase'} = $arybase;
    $self->{'ambient_warnings'} = $warning_bits;
    $self->{'ambient_hints'} = $hint_bits;
    $self->{'ambient_hinthash'} = $hinthash;
}

# This method is the inner loop, so try to keep it simple
sub deparse {
    my $self = shift;
    my($op, $cx) = @_;

    Carp::confess("Null op in deparse") if !defined($op)
					|| class($op) eq "NULL";
    my $meth = "pp_" . $op->name;
    return $self->$meth($op, $cx);
}

sub indent {
    my $self = shift;
    my $txt = shift;
    # \cK also swallows a preceding line break when followed by a
    # semicolon.
    $txt =~ s/\n\cK;//g;
    my @lines = split(/\n/, $txt);
    my $leader = "";
    my $level = 0;
    my $line;
    for $line (@lines) {
	my $cmd = substr($line, 0, 1);
	if ($cmd eq "\t" or $cmd eq "\b") {
	    $level += ($cmd eq "\t" ? 1 : -1) * $self->{'indent_size'};
	    if ($self->{'use_tabs'}) {
		$leader = "\t" x ($level / 8) . " " x ($level % 8);
	    } else {
		$leader = " " x $level;
	    }
	    $line = substr($line, 1);
	}
	if (index($line, "\f") > 0) {
		$line =~ s/\f/\n/;
	}
	if (substr($line, 0, 1) eq "\f") {
	    $line = substr($line, 1); # no indent
	} else {
	    $line = $leader . $line;
	}
	$line =~ s/\cK;?//g;
    }
    return join("\n", @lines);
}

sub pad_subs {
    my ($self, $cv) = @_;
    my $padlist = $cv->PADLIST;
    my @names = $padlist->ARRAYelt(0)->ARRAY;
    my @values = $padlist->ARRAYelt(1)->ARRAY;
    my @todo;
  PADENTRY:
    for my $ix (0.. $#names) { for $_ ($names[$ix]) {
	next if class($_) eq "SPECIAL";
	my $name = $_->PVX;
	if (defined $name && $name =~ /^&./) {
	    my $low = $_->COP_SEQ_RANGE_LOW;
	    my $flags = $_->FLAGS;
	    my $outer = $flags & PADNAMEt_OUTER;
	    if ($flags & SVpad_OUR) {
		push @todo, [$low, undef, 0, $_]
		          # [seq, no cv, not format, padname]
		    unless $outer;
		next;
	    }
	    my $protocv = $flags & SVpad_STATE
		? $values[$ix]
		: $_->PROTOCV;
	    if (class ($protocv) ne 'CV') {
		my $flags = $flags;
		my $cv = $cv;
		my $name = $_;
		while ($flags & PADNAMEt_OUTER && class ($protocv) ne 'CV')
		{
		    $cv = $cv->OUTSIDE;
		    next PADENTRY if class($cv) eq 'SPECIAL'; # XXX freed?
		    my $padlist = $cv->PADLIST;
		    my $ix = $name->PARENT_PAD_INDEX;
		    $name = $padlist->NAMES->ARRAYelt($ix);
		    $flags = $name->FLAGS;
		    $protocv = $flags & SVpad_STATE
			? $padlist->ARRAYelt(1)->ARRAYelt($ix)
			: $name->PROTOCV;
		}
	    }
	    my $defined_in_this_sub = ${$protocv->OUTSIDE} == $$cv || do {
		my $other = $protocv->PADLIST;
		$$other && $other->outid == $padlist->id;
	    };
	    if ($flags & PADNAMEt_OUTER) {
		next unless $defined_in_this_sub;
		push @todo, [$protocv->OUTSIDE_SEQ, $protocv, 0, $_];
		next;
	    }
	    my $outseq = $protocv->OUTSIDE_SEQ;
	    if ($outseq <= $low) {
		# defined before its name is visible, so it’s gotta be
		# declared and defined at once: my sub foo { ... }
		push @todo, [$low, $protocv, 0, $_];
	    }
	    else {
		# declared and defined separately: my sub f; sub f { ... }
		push @todo, [$low, undef, 0, $_];
		push @todo, [$outseq, $protocv, 0, $_]
		    if $defined_in_this_sub;
	    }
	}
    }}
    @{$self->{'subs_todo'}} =
	sort {$a->[0] <=> $b->[0]} @{$self->{'subs_todo'}}, @todo
}

sub deparse_sub {
    my $self = shift;
    my $cv = shift;
    my $proto = "";
Carp::confess("NULL in deparse_sub") if !defined($cv) || $cv->isa("B::NULL");
Carp::confess("SPECIAL in deparse_sub") if $cv->isa("B::SPECIAL");
    local $self->{'curcop'} = $self->{'curcop'};
    if ($cv->FLAGS & SVf_POK) {
	$proto = "(". $cv->PV . ") ";
    }
    if ($cv->CvFLAGS & (CVf_METHOD|CVf_LOCKED|CVf_LVALUE|CVf_ANONCONST)) {
        $proto .= ": ";
        $proto .= "lvalue " if $cv->CvFLAGS & CVf_LVALUE;
        $proto .= "locked " if $cv->CvFLAGS & CVf_LOCKED;
        $proto .= "method " if $cv->CvFLAGS & CVf_METHOD;
        $proto .= "const "  if $cv->CvFLAGS & CVf_ANONCONST;
    }

    local($self->{'curcv'}) = $cv;
    local($self->{'curcvlex'});
    local(@$self{qw'curstash warnings hints hinthash'})
		= @$self{qw'curstash warnings hints hinthash'};
    my $body;
    my $root = $cv->ROOT;
    local $B::overlay = {};
    if (not null $root) {
	$self->pad_subs($cv);
	$self->pessimise($root, $cv->START);
	my $lineseq = $root->first;
	if ($lineseq->name eq "lineseq") {
	    my @ops;
	    for(my$o=$lineseq->first; $$o; $o=$o->sibling) {
		push @ops, $o;
	    }
	    $body = $self->lineseq(undef, 0, @ops).";";
	    my $scope_en = $self->find_scope_en($lineseq);
	    if (defined $scope_en) {
		my $subs = join"", $self->seq_subs($scope_en);
		$body .= ";\n$subs" if length($subs);
	    }
	}
	else {
	    $body = $self->deparse($root->first, 0);
	}
    }
    else {
	my $sv = $cv->const_sv;
	if ($$sv) {
	    # uh-oh. inlinable sub... format it differently
	    return $proto . "{ " . $self->const($sv, 0) . " }\n";
	} else { # XSUB? (or just a declaration)
	    return "$proto;\n";
	}
    }
    return $proto ."{\n\t$body\n\b}" ."\n";
}

sub deparse_format {
    my $self = shift;
    my $form = shift;
    my @text;
    local($self->{'curcv'}) = $form;
    local($self->{'curcvlex'});
    local($self->{'in_format'}) = 1;
    local(@$self{qw'curstash warnings hints hinthash'})
		= @$self{qw'curstash warnings hints hinthash'};
    my $op = $form->ROOT;
    local $B::overlay = {};
    $self->pessimise($op, $form->START);
    my $kid;
    return "\f." if $op->first->name eq 'stub'
                || $op->first->name eq 'nextstate';
    $op = $op->first->first; # skip leavewrite, lineseq
    while (not null $op) {
	$op = $op->sibling; # skip nextstate
	my @exprs;
	$kid = $op->first->sibling; # skip pushmark
	push @text, "\f".$self->const_sv($kid)->PV;
	$kid = $kid->sibling;
	for (; not null $kid; $kid = $kid->sibling) {
	    push @exprs, $self->deparse($kid, -1);
	    $exprs[-1] =~ s/;\z//;
	}
	push @text, "\f".join(", ", @exprs)."\n" if @exprs;
	$op = $op->sibling;
    }
    return join("", @text) . "\f.";
}

sub is_scope {
    my $op = shift;
    return $op->name eq "leave" || $op->name eq "scope"
      || $op->name eq "lineseq"
	|| ($op->name eq "null" && class($op) eq "UNOP"
	    && (is_scope($op->first) || $op->first->name eq "enter"));
}

sub is_state {
    my $name = $_[0]->name;
    return $name eq "nextstate" || $name eq "dbstate" || $name eq "setstate";
}

sub is_miniwhile { # check for one-line loop ('foo() while $y--')
    my $op = shift;
    return (!null($op) and null($op->sibling)
	    and $op->name eq "null" and class($op) eq "UNOP"
	    and (($op->first->name =~ /^(and|or)$/
		  and $op->first->first->sibling->name eq "lineseq")
		 or ($op->first->name eq "lineseq"
		     and not null $op->first->first->sibling
		     and $op->first->first->sibling->name eq "unstack")
		 ));
}

# Check if the op and its sibling are the initialization and the rest of a
# for (..;..;..) { ... } loop
sub is_for_loop {
    my $op = shift;
    # This OP might be almost anything, though it won't be a
    # nextstate. (It's the initialization, so in the canonical case it
    # will be an sassign.) The sibling is (old style) a lineseq whose
    # first child is a nextstate and whose second is a leaveloop, or
    # (new style) an unstack whose sibling is a leaveloop.
    my $lseq = $op->sibling;
    return 0 unless !is_state($op) and !null($lseq);
    if ($lseq->name eq "lineseq") {
	if ($lseq->first && !null($lseq->first) && is_state($lseq->first)
	    && (my $sib = $lseq->first->sibling)) {
	    return (!null($sib) && $sib->name eq "leaveloop");
	}
    } elsif ($lseq->name eq "unstack" && ($lseq->flags & OPf_SPECIAL)) {
	my $sib = $lseq->sibling;
	return $sib && !null($sib) && $sib->name eq "leaveloop";
    }
    return 0;
}

sub is_scalar {
    my $op = shift;
    return ($op->name eq "rv2sv" or
	    $op->name eq "padsv" or
	    $op->name eq "gv" or # only in array/hash constructs
	    $op->flags & OPf_KIDS && !null($op->first)
	      && $op->first->name eq "gvsv");
}

sub maybe_parens {
    my $self = shift;
    my($text, $cx, $prec) = @_;
    if ($prec < $cx              # unary ops nest just fine
	or $prec == $cx and $cx != 4 and $cx != 16 and $cx != 21
	or $self->{'parens'})
    {
	$text = "($text)";
	# In a unop, let parent reuse our parens; see maybe_parens_unop
	$text = "\cS" . $text if $cx == 16;
	return $text;
    } else {
	return $text;
    }
}

# same as above, but get around the 'if it looks like a function' rule
sub maybe_parens_unop {
    my $self = shift;
    my($name, $kid, $cx) = @_;
    if ($cx > 16 or $self->{'parens'}) {
	$kid =  $self->deparse($kid, 1);
 	if ($name eq "umask" && $kid =~ /^\d+$/) {
	    $kid = sprintf("%#o", $kid);
	}
	return $self->keyword($name) . "($kid)";
    } else {
	$kid = $self->deparse($kid, 16);
 	if ($name eq "umask" && $kid =~ /^\d+$/) {
	    $kid = sprintf("%#o", $kid);
	}
	$name = $self->keyword($name);
	if (substr($kid, 0, 1) eq "\cS") {
	    # use kid's parens
	    return $name . substr($kid, 1);
	} elsif (substr($kid, 0, 1) eq "(") {
	    # avoid looks-like-a-function trap with extra parens
	    # ('+' can lead to ambiguities)
	    return "$name(" . $kid  . ")";
	} else {
	    return "$name $kid";
	}
    }
}

sub maybe_parens_func {
    my $self = shift;
    my($func, $text, $cx, $prec) = @_;
    if ($prec <= $cx or substr($text, 0, 1) eq "(" or $self->{'parens'}) {
	return "$func($text)";
    } else {
	return "$func $text";
    }
}

sub find_our_type {
    my ($self, $name) = @_;
    $self->populate_curcvlex() if !defined $self->{'curcvlex'};
    my $seq = $self->{'curcop'} ? $self->{'curcop'}->cop_seq : 0;
    for my $a (@{$self->{'curcvlex'}{"o$name"}}) {
	my ($st, undef, $padname) = @$a;
	if ($st >= $seq && $padname->FLAGS & SVpad_TYPED) {
	    return $padname->SvSTASH->NAME;
	}
    }
    return '';
}

sub maybe_local {
    my $self = shift;
    my($op, $cx, $text) = @_;
    my $name = $op->name;
    my $our_intro = ($name =~ /^(?:(?:gv|rv2)[ash]v|split|refassign
				  |lv(?:av)?ref)$/x)
			? OPpOUR_INTRO
			: 0;
    my $lval_intro = $name eq 'split' ? 0 : OPpLVAL_INTRO;
    # The @a in \(@a) isn't in ref context, but only when the
    # parens are there.
    my $need_parens = $self->{'in_refgen'} && $name =~ /[ah]v\z/
		   && ($op->flags & (OPf_PARENS|OPf_REF)) == OPf_PARENS;
    if ((my $priv = $op->private) & ($lval_intro|$our_intro)) {
	my @our_local;
	push @our_local, "local" if $priv & $lval_intro;
	push @our_local, "our"   if $priv & $our_intro;
	my $our_local = join " ", map $self->keyword($_), @our_local;
	if( $our_local[-1] eq 'our' ) {
	    if ( $text !~ /^\W(\w+::)*\w+\z/
	     and !utf8::decode($text) || $text !~ /^\W(\w+::)*\w+\z/
	    ) {
		die "Unexpected our($text)\n";
	    }
	    $text =~ s/(\w+::)+//;

	    if (my $type = $self->find_our_type($text)) {
		$our_local .= ' ' . $type;
	    }
	}
	return $need_parens ? "($text)" : $text
	    if $self->{'avoid_local'}{$$op};
	if ($need_parens) {
	    return "$our_local($text)";
	} elsif (want_scalar($op)) {
	    return "$our_local $text";
	} else {
	    return $self->maybe_parens_func("$our_local", $text, $cx, 16);
	}
    } else {
	return $need_parens ? "($text)" : $text;
    }
}

sub maybe_targmy {
    my $self = shift;
    my($op, $cx, $func, @args) = @_;
    if ($op->private & OPpTARGET_MY) {
	my $var = $self->padname($op->targ);
	my $val = $func->($self, $op, 7, @args);
	return $self->maybe_parens("$var = $val", $cx, 7);
    } else {
	return $func->($self, $op, $cx, @args);
    }
}

sub padname_sv {
    my $self = shift;
    my $targ = shift;
    return $self->{'curcv'}->PADLIST->ARRAYelt(0)->ARRAYelt($targ);
}

sub maybe_my {
    my $self = shift;
    my($op, $cx, $text, $padname, $forbid_parens) = @_;
    # The @a in \(@a) isn't in ref context, but only when the
    # parens are there.
    my $need_parens = !$forbid_parens && $self->{'in_refgen'}
		   && $op->name =~ /[ah]v\z/
		   && ($op->flags & (OPf_PARENS|OPf_REF)) == OPf_PARENS;
    # The @a in \my @a must not have parens.
    if (!$need_parens && $self->{'in_refgen'}) {
	$forbid_parens = 1;
    }
    if ($op->private & OPpLVAL_INTRO and not $self->{'avoid_local'}{$$op}) {
	# Check $padname->FLAGS for statehood, rather than $op->private,
	# because enteriter ops do not carry the flag.
	my $my =
	    $self->keyword($padname->FLAGS & SVpad_STATE ? "state" : "my");
	if ($padname->FLAGS & SVpad_TYPED) {
	    $my .= ' ' . $padname->SvSTASH->NAME;
	}
	if ($need_parens) {
	    return "$my($text)";
	} elsif ($forbid_parens || want_scalar($op)) {
	    return "$my $text";
	} else {
	    return $self->maybe_parens_func($my, $text, $cx, 16);
	}
    } else {
	return $need_parens ? "($text)" : $text;
    }
}

# The following OPs don't have functions:

# pp_padany -- does not exist after parsing

sub AUTOLOAD {
    if ($AUTOLOAD =~ s/^.*::pp_//) {
	warn "unexpected OP_".
	  ($_[1]->type == OP_CUSTOM ? "CUSTOM ($AUTOLOAD)" : uc $AUTOLOAD);
	return "XXX";
    } else {
	die "Undefined subroutine $AUTOLOAD called";
    }
}

sub DESTROY {}	#	Do not AUTOLOAD

# $root should be the op which represents the root of whatever
# we're sequencing here. If it's undefined, then we don't append
# any subroutine declarations to the deparsed ops, otherwise we
# append appropriate declarations.
sub lineseq {
    my($self, $root, $cx, @ops) = @_;
    my($expr, @exprs);

    my $out_cop = $self->{'curcop'};
    my $out_seq = defined($out_cop) ? $out_cop->cop_seq : undef;
    my $limit_seq;
    if (defined $root) {
	$limit_seq = $out_seq;
	my $nseq;
	$nseq = $self->find_scope_st($root->sibling) if ${$root->sibling};
	$limit_seq = $nseq if !defined($limit_seq)
			   or defined($nseq) && $nseq < $limit_seq;
    }
    $limit_seq = $self->{'limit_seq'}
	if defined($self->{'limit_seq'})
	&& (!defined($limit_seq) || $self->{'limit_seq'} < $limit_seq);
    local $self->{'limit_seq'} = $limit_seq;

    $self->walk_lineseq($root, \@ops,
		       sub { push @exprs, $_[0]} );

    my $sep = $cx ? '; ' : ";\n";
    my $body = join($sep, grep {length} @exprs);
    my $subs = "";
    if (defined $root && defined $limit_seq && !$self->{'in_format'}) {
	$subs = join "\n", $self->seq_subs($limit_seq);
    }
    return join($sep, grep {length} $body, $subs);
}

sub scopeop {
    my($real_block, $self, $op, $cx) = @_;
    my $kid;
    my @kids;

    local(@$self{qw'curstash warnings hints hinthash'})
		= @$self{qw'curstash warnings hints hinthash'} if $real_block;
    if ($real_block) {
	$kid = $op->first->sibling; # skip enter
	if (is_miniwhile($kid)) {
	    my $top = $kid->first;
	    my $name = $top->name;
	    if ($name eq "and") {
		$name = $self->keyword("while");
	    } elsif ($name eq "or") {
		$name = $self->keyword("until");
	    } else { # no conditional -> while 1 or until 0
		return $self->deparse($top->first, 1) . " "
		     . $self->keyword("while") . " 1";
	    }
	    my $cond = $top->first;
	    my $body = $cond->sibling->first; # skip lineseq
	    $cond = $self->deparse($cond, 1);
	    $body = $self->deparse($body, 1);
	    return "$body $name $cond";
	}
    } else {
	$kid = $op->first;
    }
    for (; !null($kid); $kid = $kid->sibling) {
	push @kids, $kid;
    }
    if ($cx > 0) { # inside an expression, (a do {} while for lineseq)
	my $body = $self->lineseq($op, 0, @kids);
	return is_lexical_subs(@kids)
		? $body
		: ($self->lex_in_scope("&do") ? "CORE::do" : "do")
		 . " {\n\t$body\n\b}";
    } else {
	my $lineseq = $self->lineseq($op, $cx, @kids);
	return (length ($lineseq) ? "$lineseq;" : "");
    }
}

sub pp_scope { scopeop(0, @_); }
sub pp_lineseq { scopeop(0, @_); }
sub pp_leave { scopeop(1, @_); }

# This is a special case of scopeop and lineseq, for the case of the
# main_root. The difference is that we print the output statements as
# soon as we get them, for the sake of impatient users.
sub deparse_root {
    my $self = shift;
    my($op) = @_;
    local(@$self{qw'curstash warnings hints hinthash'})
      = @$self{qw'curstash warnings hints hinthash'};
    my @kids;
    return if null $op->first; # Can happen, e.g., for Bytecode without -k
    for (my $kid = $op->first->sibling; !null($kid); $kid = $kid->sibling) {
	push @kids, $kid;
    }
    $self->walk_lineseq($op, \@kids,
			sub { return unless length $_[0];
			      print $self->indent($_[0].';');
			      print "\n"
				unless $_[1] == $#kids;
			  });
}

sub walk_lineseq {
    my ($self, $op, $kids, $callback) = @_;
    my @kids = @$kids;
    for (my $i = 0; $i < @kids; $i++) {
	my $expr = "";
	if (is_state $kids[$i]) {
	    $expr = $self->deparse($kids[$i++], 0);
	    if ($i > $#kids) {
		$callback->($expr, $i);
		last;
	    }
	}
	if (is_for_loop($kids[$i])) {
	    $callback->($expr . $self->for_loop($kids[$i], 0),
		$i += $kids[$i]->sibling->name eq "unstack" ? 2 : 1);
	    next;
	}
	my $expr2 = $self->deparse($kids[$i], (@kids != 1)/2);
	$expr2 =~ s/^sub :(?!:)/+sub :/; # statement label otherwise
	$expr .= $expr2;
	$callback->($expr, $i);
    }
}

# The BEGIN {} is used here because otherwise this code isn't executed
# when you run B::Deparse on itself.
my %globalnames;
BEGIN { map($globalnames{$_}++, "SIG", "STDIN", "STDOUT", "STDERR", "INC",
	    "ENV", "ARGV", "ARGVOUT", "_"); }

sub gv_name {
    my $self = shift;
    my $gv = shift;
    my $raw = shift;
#Carp::confess() unless ref($gv) eq "B::GV";
    my $cv = $gv->FLAGS & SVf_ROK ? $gv->RV : 0;
    my $stash = ($cv || $gv)->STASH->NAME;
    my $name = $raw
	? $cv ? $cv->NAME_HEK || $cv->GV->NAME : $gv->NAME
	: $cv
	    ? B::safename($cv->NAME_HEK || $cv->GV->NAME)
	    : $gv->SAFENAME;
    if ($stash eq 'main' && $name =~ /^::/) {
	$stash = '::';
    }
    elsif (($stash eq 'main'
	    && ($globalnames{$name} || $name =~ /^[^A-Za-z_:]/))
	or ($stash eq $self->{'curstash'} && !$globalnames{$name}
	    && ($stash eq 'main' || $name !~ /::/))
	  )
    {
	$stash = "";
    } else {
	$stash = $stash . "::";
    }
    if (!$raw and $name =~ /^(\^..|{)/) {
        $name = "{$name}";       # ${^WARNING_BITS}, etc and ${
    }
    return $stash . $name;
}

# Return the name to use for a stash variable.
# If a lexical with the same name is in scope, or
# if strictures are enabled, it may need to be
# fully-qualified.
sub stash_variable {
    my ($self, $prefix, $name, $cx) = @_;

    return "$prefix$name" if $name =~ /::/;

    unless ($prefix eq '$' || $prefix eq '@' || $prefix eq '&' || #'
	    $prefix eq '%' || $prefix eq '$#') {
	return "$prefix$name";
    }

    if ($name =~ /^[^[:alpha:]_+-]$/) {
      if (defined $cx && $cx == 26) {
	if ($prefix eq '@') {
	    return "$prefix\{$name}";
	}
	elsif ($name eq '#') { return '${#}' } #  "${#}a" vs "$#a"
      }
      if ($prefix eq '$#') {
	return "\$#{$name}";
      }
    }

    return $prefix . $self->maybe_qualify($prefix, $name);
}

my %unctrl = # portable to EBCDIC
    (
     "\c@" => '@',	# unused
     "\cA" => 'A',
     "\cB" => 'B',
     "\cC" => 'C',
     "\cD" => 'D',
     "\cE" => 'E',
     "\cF" => 'F',
     "\cG" => 'G',
     "\cH" => 'H',
     "\cI" => 'I',
     "\cJ" => 'J',
     "\cK" => 'K',
     "\cL" => 'L',
     "\cM" => 'M',
     "\cN" => 'N',
     "\cO" => 'O',
     "\cP" => 'P',
     "\cQ" => 'Q',
     "\cR" => 'R',
     "\cS" => 'S',
     "\cT" => 'T',
     "\cU" => 'U',
     "\cV" => 'V',
     "\cW" => 'W',
     "\cX" => 'X',
     "\cY" => 'Y',
     "\cZ" => 'Z',
     "\c[" => '[',	# unused
     "\c\\" => '\\',	# unused
     "\c]" => ']',	# unused
     "\c_" => '_',	# unused
    );

# Return just the name, without the prefix.  It may be returned as a quoted
# string.  The second return value is a boolean indicating that.
sub stash_variable_name {
    my($self, $prefix, $gv) = @_;
    my $name = $self->gv_name($gv, 1);
    $name = $self->maybe_qualify($prefix,$name);
    if ($name =~ /^(?:\S|(?!\d)[\ca-\cz]?(?:\w|::)*|\d+)\z/) {
	$name =~ s/^([\ca-\cz])/'^' . $unctrl{$1}/e;
	$name =~ /^(\^..|{)/ and $name = "{$name}";
	return $name, 0; # not quoted
    }
    else {
	single_delim("q", "'", $name, $self), 1;
    }
}

sub maybe_qualify {
    my ($self,$prefix,$name) = @_;
    my $v = ($prefix eq '$#' ? '@' : $prefix) . $name;
    return $name if !$prefix || $name =~ /::/;
    return $self->{'curstash'}.'::'. $name
	if
	    $name =~ /^(?!\d)\w/         # alphabetic
	 && $v    !~ /^\$[ab]\z/	 # not $a or $b
	 && !$globalnames{$name}         # not a global name
	 && $self->{hints} & $strict_bits{vars}  # strict vars
	 && !$self->lex_in_scope($v,1)   # no "our"
      or $self->lex_in_scope($v);        # conflicts with "my" variable
    return $name;
}

sub lex_in_scope {
    my ($self, $name, $our) = @_;
    substr $name, 0, 0, = $our ? 'o' : 'm'; # our/my
    $self->populate_curcvlex() if !defined $self->{'curcvlex'};

    return 0 if !defined($self->{'curcop'});
    my $seq = $self->{'curcop'}->cop_seq;
    return 0 if !exists $self->{'curcvlex'}{$name};
    for my $a (@{$self->{'curcvlex'}{$name}}) {
	my ($st, $en) = @$a;
	return 1 if $seq > $st && $seq <= $en;
    }
    return 0;
}

sub populate_curcvlex {
    my $self = shift;
    for (my $cv = $self->{'curcv'}; class($cv) eq "CV"; $cv = $cv->OUTSIDE) {
	my $padlist = $cv->PADLIST;
	# an undef CV still in lexical chain
	next if class($padlist) eq "SPECIAL";
	my @padlist = $padlist->ARRAY;
	my @ns = $padlist[0]->ARRAY;

	for (my $i=0; $i<@ns; ++$i) {
	    next if class($ns[$i]) eq "SPECIAL";
	    if (class($ns[$i]) eq "PV") {
		# Probably that pesky lexical @_
		next;
	    }
            my $name = $ns[$i]->PVX;
	    next unless defined $name;
	    my ($seq_st, $seq_en) =
		($ns[$i]->FLAGS & SVf_FAKE)
		    ? (0, 999999)
		    : ($ns[$i]->COP_SEQ_RANGE_LOW, $ns[$i]->COP_SEQ_RANGE_HIGH);

	    push @{$self->{'curcvlex'}{
			($ns[$i]->FLAGS & SVpad_OUR ? 'o' : 'm') . $name
		  }}, [$seq_st, $seq_en, $ns[$i]];
	}
    }
}

sub find_scope_st { ((find_scope(@_))[0]); }
sub find_scope_en { ((find_scope(@_))[1]); }

# Recurses down the tree, looking for pad variable introductions and COPs
sub find_scope {
    my ($self, $op, $scope_st, $scope_en) = @_;
    carp("Undefined op in find_scope") if !defined $op;
    return ($scope_st, $scope_en) unless $op->flags & OPf_KIDS;

    my @queue = ($op);
    while(my $op = shift @queue ) {
	for (my $o=$op->first; $$o; $o=$o->sibling) {
	    if ($o->name =~ /^pad.v$/ && $o->private & OPpLVAL_INTRO) {
		my $s = int($self->padname_sv($o->targ)->COP_SEQ_RANGE_LOW);
		my $e = $self->padname_sv($o->targ)->COP_SEQ_RANGE_HIGH;
		$scope_st = $s if !defined($scope_st) || $s < $scope_st;
		$scope_en = $e if !defined($scope_en) || $e > $scope_en;
		return ($scope_st, $scope_en);
	    }
	    elsif (is_state($o)) {
		my $c = $o->cop_seq;
		$scope_st = $c if !defined($scope_st) || $c < $scope_st;
		$scope_en = $c if !defined($scope_en) || $c > $scope_en;
		return ($scope_st, $scope_en);
	    }
	    elsif ($o->flags & OPf_KIDS) {
		unshift (@queue, $o);
	    }
	}
    }

    return ($scope_st, $scope_en);
}

# Returns a list of subs which should be inserted before the COP
sub cop_subs {
    my ($self, $op, $out_seq) = @_;
    my $seq = $op->cop_seq;
    if ($] < 5.021006) {
      # If we have nephews, then our sequence number indicates
      # the cop_seq of the end of some sort of scope.
      if (class($op->sibling) ne "NULL" && $op->sibling->flags & OPf_KIDS
	and my $nseq = $self->find_scope_st($op->sibling) ) {
	$seq = $nseq;
      }
    }
    $seq = $out_seq if defined($out_seq) && $out_seq < $seq;
    return $self->seq_subs($seq);
}

sub seq_subs {
    my ($self, $seq) = @_;
    my @text;
#push @text, "# ($seq)\n";

    return "" if !defined $seq;
    my @pending;
    while (scalar(@{$self->{'subs_todo'}})
	   and $seq > $self->{'subs_todo'}[0][0]) {
	my $cv = $self->{'subs_todo'}[0][1];
	# Skip the OUTSIDE check for lexical subs.  We may be deparsing a
	# cloned anon sub with lexical subs declared in it, in which case
	# the OUTSIDE pointer points to the anon protosub.
	my $lexical = ref $self->{'subs_todo'}[0][3];
	my $outside = !$lexical && $cv && $cv->OUTSIDE;
	if (!$lexical and $cv
	 and ${$cv->OUTSIDE || \0} != ${$self->{'curcv'}})
	{
	    push @pending, shift @{$self->{'subs_todo'}};
	    next;
	}
	push @text, $self->next_todo;
    }
    unshift @{$self->{'subs_todo'}}, @pending;
    return @text;
}

sub _features_from_bundle {
    my ($hints, $hh) = @_;
    foreach (@{$feature::feature_bundle{@feature::hint_bundles[$hints >> $feature::hint_shift]}}) {
	$hh->{$feature::feature{$_}} = 1;
    }
    return $hh;
}

# Notice how subs and formats are inserted between statements here;
# also $[ assignments and pragmas.
sub pp_nextstate {
    my $self = shift;
    my($op, $cx) = @_;
    $self->{'curcop'} = $op;
    my @text;
    push @text, $self->cop_subs($op);
    if (@text) {
	# Special marker to swallow up the semicolon
	push @text, "\cK";
    }
    my $stash = $op->stashpv;
    if ($stash ne $self->{'curstash'}) {
	push @text, $self->keyword("package") . " $stash;\n";
	$self->{'curstash'} = $stash;
    }

    if (OPpCONST_ARYBASE && $self->{'arybase'} != $op->arybase) {
	push @text, '$[ = '. $op->arybase .";\n";
	$self->{'arybase'} = $op->arybase;
    }

    my $warnings = $op->warnings;
    my $warning_bits;
    if ($warnings->isa("B::SPECIAL") && $$warnings == 4) {
	$warning_bits = $warnings::Bits{"all"} & WARN_MASK;
    }
    elsif ($warnings->isa("B::SPECIAL") && $$warnings == 5) {
        $warning_bits = $warnings::NONE;
    }
    elsif ($warnings->isa("B::SPECIAL")) {
	$warning_bits = undef;
    }
    else {
	$warning_bits = $warnings->PV & WARN_MASK;
    }

    if (defined ($warning_bits) and
       !defined($self->{warnings}) || $self->{'warnings'} ne $warning_bits) {
	push @text,
	    $self->declare_warnings($self->{'warnings'}, $warning_bits);
	$self->{'warnings'} = $warning_bits;
    }

    my $hints = $] < 5.008009 ? $op->private : $op->hints;
    my $old_hints = $self->{'hints'};
    if ($self->{'hints'} != $hints) {
	push @text, $self->declare_hints($self->{'hints'}, $hints);
	$self->{'hints'} = $hints;
    }

    my $newhh;
    if ($] > 5.009) {
	$newhh = $op->hints_hash->HASH;
    }

    if ($] >= 5.015006) {
	# feature bundle hints
	my $from = $old_hints & $feature::hint_mask;
	my $to   = $    hints & $feature::hint_mask;
	if ($from != $to) {
	    if ($to == $feature::hint_mask) {
		if ($self->{'hinthash'}) {
		    delete $self->{'hinthash'}{$_}
			for grep /^feature_/, keys %{$self->{'hinthash'}};
		}
		else { $self->{'hinthash'} = {} }
		$self->{'hinthash'}
		    = _features_from_bundle($from, $self->{'hinthash'});
	    }
	    else {
		my $bundle =
		    $feature::hint_bundles[$to >> $feature::hint_shift];
		$bundle =~ s/(\d[13579])\z/$1+1/e; # 5.11 => 5.12
		push @text,
		    $self->keyword("no") . " feature ':all';\n",
		    $self->keyword("use") . " feature ':$bundle';\n";
	    }
	}
    }

    if ($] > 5.009) {
	push @text, $self->declare_hinthash(
	    $self->{'hinthash'}, $newhh,
	    $self->{indent_size}, $self->{hints},
	);
	$self->{'hinthash'} = $newhh;
    }

    # This should go after of any branches that add statements, to
    # increase the chances that it refers to the same line it did in
    # the original program.
    if ($self->{'linenums'} && $cx != .5) { # $cx == .5 means in a format
	push @text, "\f#line " . $op->line .
	  ' "' . $op->file, qq'"\n';
    }

    push @text, $op->label . ": " if $op->label;

    return join("", @text);
}

sub declare_warnings {
    my ($self, $from, $to) = @_;
    if (($to & WARN_MASK) eq (warnings::bits("all") & WARN_MASK)) {
	return $self->keyword("use") . " warnings;\n";
    }
    elsif (($to & WARN_MASK) eq ("\0"x length($to) & WARN_MASK)) {
	return $self->keyword("no") . " warnings;\n";
    }
    return "BEGIN {\${^WARNING_BITS} = \""
           . join("", map { sprintf("\\x%02x", ord $_) } split "", $to)
           . "\"}\n\cK";
}

sub declare_hints {
    my ($self, $from, $to) = @_;
    my $use = $to   & ~$from;
    my $no  = $from & ~$to;
    my $decls = "";
    for my $pragma (hint_pragmas($use)) {
	$decls .= $self->keyword("use") . " $pragma;\n";
    }
    for my $pragma (hint_pragmas($no)) {
        $decls .= $self->keyword("no") . " $pragma;\n";
    }
    return $decls;
}

# Internal implementation hints that the core sets automatically, so don't need
# (or want) to be passed back to the user
my %ignored_hints = (
    'open<' => 1,
    'open>' => 1,
    ':'     => 1,
    'strict/refs' => 1,
    'strict/subs' => 1,
    'strict/vars' => 1,
);

my %rev_feature;

sub declare_hinthash {
    my ($self, $from, $to, $indent, $hints) = @_;
    my $doing_features =
	($hints & $feature::hint_mask) == $feature::hint_mask;
    my @decls;
    my @features;
    my @unfeatures; # bugs?
    for my $key (sort keys %$to) {
	next if $ignored_hints{$key};
	my $is_feature = $key =~ /^feature_/ && $^V ge 5.15.6;
	next if $is_feature and not $doing_features;
	if (!exists $from->{$key} or $from->{$key} ne $to->{$key}) {
	    push(@features, $key), next if $is_feature;
	    push @decls,
		qq(\$^H{) . single_delim("q", "'", $key, $self) . qq(} = )
	      . (
		   defined $to->{$key}
			? single_delim("q", "'", $to->{$key}, $self)
			: 'undef'
		)
	      . qq(;);
	}
    }
    for my $key (sort keys %$from) {
	next if $ignored_hints{$key};
	my $is_feature = $key =~ /^feature_/ && $^V ge 5.15.6;
	next if $is_feature and not $doing_features;
	if (!exists $to->{$key}) {
	    push(@unfeatures, $key), next if $is_feature;
	    push @decls, qq(delete \$^H{'$key'};);
	}
    }
    my @ret;
    if (@features || @unfeatures) {
	if (!%rev_feature) { %rev_feature = reverse %feature::feature }
    }
    if (@features) {
	push @ret, $self->keyword("use") . " feature "
		 . join(", ", map "'$rev_feature{$_}'", @features) . ";\n";
    }
    if (@unfeatures) {
	push @ret, $self->keyword("no") . " feature "
		 . join(", ", map "'$rev_feature{$_}'", @unfeatures)
		 . ";\n";
    }
    @decls and
	push @ret,
	     join("\n" . (" " x $indent), "BEGIN {", @decls) . "\n}\n\cK";
    return @ret;
}

sub hint_pragmas {
    my ($bits) = @_;
    my (@pragmas, @strict);
    push @pragmas, "integer" if $bits & 0x1;
    for (sort keys %strict_bits) {
	push @strict, "'$_'" if $bits & $strict_bits{$_};
    }
    if (@strict == keys %strict_bits) {
	push @pragmas, "strict";
    }
    elsif (@strict) {
	push @pragmas, "strict " . join ', ', @strict;
    }
    push @pragmas, "bytes" if $bits & 0x8;
    return @pragmas;
}

sub pp_dbstate { pp_nextstate(@_) }
sub pp_setstate { pp_nextstate(@_) }

sub pp_unstack { return "" } # see also leaveloop

my %feature_keywords = (
  # keyword => 'feature',
    state   => 'state',
    say     => 'say',
    given   => 'switch',
    when    => 'switch',
    default => 'switch',
    break   => 'switch',
    evalbytes=>'evalbytes',
    __SUB__ => '__SUB__',
   fc       => 'fc',
);

# keywords that are strong and also have a prototype
#
my %strong_proto_keywords = map { $_ => 1 } qw(
    pos
    prototype
    scalar
    study
    undef
);

sub feature_enabled {
	my($self,$name) = @_;
	my $hh;
	my $hints = $self->{hints} & $feature::hint_mask;
	if ($hints && $hints != $feature::hint_mask) {
	    $hh = _features_from_bundle($hints);
	}
	elsif ($hints) { $hh = $self->{'hinthash'} }
	return $hh && $hh->{"feature_$feature_keywords{$name}"}
}

sub keyword {
    my $self = shift;
    my $name = shift;
    return $name if $name =~ /^CORE::/; # just in case
    if (exists $feature_keywords{$name}) {
	return "CORE::$name" if not $self->feature_enabled($name);
    }
    # This sub may be called for a program that has no nextstate ops.  In
    # that case we may have a lexical sub named no/use/sub in scope but
    # but $self->lex_in_scope will return false because it depends on the
    # current nextstate op.  So we need this alternate method if there is
    # no current cop.
    if (!$self->{'curcop'}) {
	$self->populate_curcvlex() if !defined $self->{'curcvlex'};
	return "CORE::$name" if exists $self->{'curcvlex'}{"m&$name"}
			     || exists $self->{'curcvlex'}{"o&$name"};
    } elsif ($self->lex_in_scope("&$name")
	  || $self->lex_in_scope("&$name", 1)) {
	return "CORE::$name";
    }
    if ($strong_proto_keywords{$name}
        || ($name !~ /^(?:chom?p|do|exec|glob|s(?:elect|ystem))\z/
	    && !defined eval{prototype "CORE::$name"})
    ) { return $name }
    if (
	exists $self->{subs_declared}{$name}
	 or
	exists &{"$self->{curstash}::$name"}
    ) {
	return "CORE::$name"
    }
    return $name;
}

sub baseop {
    my $self = shift;
    my($op, $cx, $name) = @_;
    return $self->keyword($name);
}

sub pp_stub { "()" }
sub pp_wantarray { baseop(@_, "wantarray") }
sub pp_fork { baseop(@_, "fork") }
sub pp_wait { maybe_targmy(@_, \&baseop, "wait") }
sub pp_getppid { maybe_targmy(@_, \&baseop, "getppid") }
sub pp_time { maybe_targmy(@_, \&baseop, "time") }
sub pp_tms { baseop(@_, "times") }
sub pp_ghostent { baseop(@_, "gethostent") }
sub pp_gnetent { baseop(@_, "getnetent") }
sub pp_gprotoent { baseop(@_, "getprotoent") }
sub pp_gservent { baseop(@_, "getservent") }
sub pp_ehostent { baseop(@_, "endhostent") }
sub pp_enetent { baseop(@_, "endnetent") }
sub pp_eprotoent { baseop(@_, "endprotoent") }
sub pp_eservent { baseop(@_, "endservent") }
sub pp_gpwent { baseop(@_, "getpwent") }
sub pp_spwent { baseop(@_, "setpwent") }
sub pp_epwent { baseop(@_, "endpwent") }
sub pp_ggrent { baseop(@_, "getgrent") }
sub pp_sgrent { baseop(@_, "setgrent") }
sub pp_egrent { baseop(@_, "endgrent") }
sub pp_getlogin { baseop(@_, "getlogin") }

sub POSTFIX () { 1 }

# I couldn't think of a good short name, but this is the category of
# symbolic unary operators with interesting precedence

sub pfixop {
    my $self = shift;
    my($op, $cx, $name, $prec, $flags) = (@_, 0);
    my $kid = $op->first;
    $kid = $self->deparse($kid, $prec);
    return $self->maybe_parens(($flags & POSTFIX)
				 ? "$kid$name"
				   # avoid confusion with filetests
				 : $name eq '-'
				   && $kid =~ /^[a-zA-Z](?!\w)/
					? "$name($kid)"
					: "$name$kid",
			       $cx, $prec);
}

sub pp_preinc { pfixop(@_, "++", 23) }
sub pp_predec { pfixop(@_, "--", 23) }
sub pp_postinc { maybe_targmy(@_, \&pfixop, "++", 23, POSTFIX) }
sub pp_postdec { maybe_targmy(@_, \&pfixop, "--", 23, POSTFIX) }
sub pp_i_preinc { pfixop(@_, "++", 23) }
sub pp_i_predec { pfixop(@_, "--", 23) }
sub pp_i_postinc { maybe_targmy(@_, \&pfixop, "++", 23, POSTFIX) }
sub pp_i_postdec { maybe_targmy(@_, \&pfixop, "--", 23, POSTFIX) }
sub pp_complement { maybe_targmy(@_, \&pfixop, "~", 21) }
*pp_ncomplement = *pp_complement;
sub pp_scomplement { maybe_targmy(@_, \&pfixop, "~.", 21) }

sub pp_negate { maybe_targmy(@_, \&real_negate) }
sub real_negate {
    my $self = shift;
    my($op, $cx) = @_;
    if ($op->first->name =~ /^(i_)?negate$/) {
	# avoid --$x
	$self->pfixop($op, $cx, "-", 21.5);
    } else {
	$self->pfixop($op, $cx, "-", 21);	
    }
}
sub pp_i_negate { pp_negate(@_) }

sub pp_not {
    my $self = shift;
    my($op, $cx) = @_;
    if ($cx <= 4) {
	$self->listop($op, $cx, "not", $op->first);
    } else {
	$self->pfixop($op, $cx, "!", 21);	
    }
}

sub unop {
    my $self = shift;
    my($op, $cx, $name, $nollafr) = @_;
    my $kid;
    if ($op->flags & OPf_KIDS) {
	$kid = $op->first;
 	if (not $name) {
 	    # this deals with 'boolkeys' right now
 	    return $self->deparse($kid,$cx);
 	}
	my $builtinname = $name;
	$builtinname =~ /^CORE::/ or $builtinname = "CORE::$name";
	if (defined prototype($builtinname)
	   && $builtinname ne 'CORE::readline'
	   && prototype($builtinname) =~ /^;?\*/
	   && $kid->name eq "rv2gv") {
	    $kid = $kid->first;
	}

	if ($nollafr) {
	    if (($kid = $self->deparse($kid, 16)) !~ s/^\cS//) {
		# require foo() is a syntax error.
		$kid =~ /^(?!\d)\w/ and $kid = "($kid)";
	    }
	    return $self->maybe_parens(
			$self->keyword($name) . " $kid", $cx, 16
		   );
	}   
	return $self->maybe_parens_unop($name, $kid, $cx);
    } else {
	return $self->maybe_parens(
	    $self->keyword($name) . ($op->flags & OPf_SPECIAL ? "()" : ""),
	    $cx, 16,
	);
    }
}

sub pp_chop { maybe_targmy(@_, \&unop, "chop") }
sub pp_chomp { maybe_targmy(@_, \&unop, "chomp") }
sub pp_schop { maybe_targmy(@_, \&unop, "chop") }
sub pp_schomp { maybe_targmy(@_, \&unop, "chomp") }
sub pp_defined { unop(@_, "defined") }
sub pp_undef { unop(@_, "undef") }
sub pp_study { unop(@_, "study") }
sub pp_ref { unop(@_, "ref") }
sub pp_pos { maybe_local(@_, unop(@_, "pos")) }

sub pp_sin { maybe_targmy(@_, \&unop, "sin") }
sub pp_cos { maybe_targmy(@_, \&unop, "cos") }
sub pp_rand { maybe_targmy(@_, \&unop, "rand") }
sub pp_srand { unop(@_, "srand") }
sub pp_exp { maybe_targmy(@_, \&unop, "exp") }
sub pp_log { maybe_targmy(@_, \&unop, "log") }
sub pp_sqrt { maybe_targmy(@_, \&unop, "sqrt") }
sub pp_int { maybe_targmy(@_, \&unop, "int") }
sub pp_hex { maybe_targmy(@_, \&unop, "hex") }
sub pp_oct { maybe_targmy(@_, \&unop, "oct") }
sub pp_abs { maybe_targmy(@_, \&unop, "abs") }

sub pp_length { maybe_targmy(@_, \&unop, "length") }
sub pp_ord { maybe_targmy(@_, \&unop, "ord") }
sub pp_chr { maybe_targmy(@_, \&unop, "chr") }

sub pp_each { unop(@_, "each") }
sub pp_values { unop(@_, "values") }
sub pp_keys { unop(@_, "keys") }
{ no strict 'refs'; *{"pp_r$_"} = *{"pp_$_"} for qw< keys each values >; }
sub pp_boolkeys { 
    # no name because its an optimisation op that has no keyword
    unop(@_,"");
}
sub pp_aeach { unop(@_, "each") }
sub pp_avalues { unop(@_, "values") }
sub pp_akeys { unop(@_, "keys") }
sub pp_pop { unop(@_, "pop") }
sub pp_shift { unop(@_, "shift") }

sub pp_caller { unop(@_, "caller") }
sub pp_reset { unop(@_, "reset") }
sub pp_exit { unop(@_, "exit") }
sub pp_prototype { unop(@_, "prototype") }

sub pp_close { unop(@_, "close") }
sub pp_fileno { unop(@_, "fileno") }
sub pp_umask { unop(@_, "umask") }
sub pp_untie { unop(@_, "untie") }
sub pp_tied { unop(@_, "tied") }
sub pp_dbmclose { unop(@_, "dbmclose") }
sub pp_getc { unop(@_, "getc") }
sub pp_eof { unop(@_, "eof") }
sub pp_tell { unop(@_, "tell") }
sub pp_getsockname { unop(@_, "getsockname") }
sub pp_getpeername { unop(@_, "getpeername") }

sub pp_chdir {
    my ($self, $op, $cx) = @_;
    if (($op->flags & (OPf_SPECIAL|OPf_KIDS)) == (OPf_SPECIAL|OPf_KIDS)) {
	my $kw = $self->keyword("chdir");
	my $kid = $self->const_sv($op->first)->PV;
	my $code = $kw
		 . ($cx >= 16 || $self->{'parens'} ? "($kid)" : " $kid");
	maybe_targmy(@_, sub { $_[3] }, $code);
    } else {
	maybe_targmy(@_, \&unop, "chdir")
    }
}

sub pp_chroot { maybe_targmy(@_, \&unop, "chroot") }
sub pp_readlink { unop(@_, "readlink") }
sub pp_rmdir { maybe_targmy(@_, \&unop, "rmdir") }
sub pp_readdir { unop(@_, "readdir") }
sub pp_telldir { unop(@_, "telldir") }
sub pp_rewinddir { unop(@_, "rewinddir") }
sub pp_closedir { unop(@_, "closedir") }
sub pp_getpgrp { maybe_targmy(@_, \&unop, "getpgrp") }
sub pp_localtime { unop(@_, "localtime") }
sub pp_gmtime { unop(@_, "gmtime") }
sub pp_alarm { unop(@_, "alarm") }
sub pp_sleep { maybe_targmy(@_, \&unop, "sleep") }

sub pp_dofile {
    my $code = unop(@_, "do", 1); # llafr does not apply
    if ($code =~ s/^((?:CORE::)?do) \{/$1({/) { $code .= ')' }
    $code;
}
sub pp_entereval {
    unop(
      @_,
      $_[1]->private & OPpEVAL_BYTES ? 'evalbytes' : "eval"
    )
}

sub pp_ghbyname { unop(@_, "gethostbyname") }
sub pp_gnbyname { unop(@_, "getnetbyname") }
sub pp_gpbyname { unop(@_, "getprotobyname") }
sub pp_shostent { unop(@_, "sethostent") }
sub pp_snetent { unop(@_, "setnetent") }
sub pp_sprotoent { unop(@_, "setprotoent") }
sub pp_sservent { unop(@_, "setservent") }
sub pp_gpwnam { unop(@_, "getpwnam") }
sub pp_gpwuid { unop(@_, "getpwuid") }
sub pp_ggrnam { unop(@_, "getgrnam") }
sub pp_ggrgid { unop(@_, "getgrgid") }

sub pp_lock { unop(@_, "lock") }

sub pp_continue { unop(@_, "continue"); }
sub pp_break { unop(@_, "break"); }

sub givwhen {
    my $self = shift;
    my($op, $cx, $givwhen) = @_;

    my $enterop = $op->first;
    my ($head, $block);
    if ($enterop->flags & OPf_SPECIAL) {
	$head = $self->keyword("default");
	$block = $self->deparse($enterop->first, 0);
    }
    else {
	my $cond = $enterop->first;
	my $cond_str = $self->deparse($cond, 1);
	$head = "$givwhen ($cond_str)";
	$block = $self->deparse($cond->sibling, 0);
    }

    return "$head {\n".
	"\t$block\n".
	"\b}\cK";
}

sub pp_leavegiven { givwhen(@_, $_[0]->keyword("given")); }
sub pp_leavewhen  { givwhen(@_, $_[0]->keyword("when")); }

sub pp_exists {
    my $self = shift;
    my($op, $cx) = @_;
    my $arg;
    my $name = $self->keyword("exists");
    if ($op->private & OPpEXISTS_SUB) {
	# Checking for the existence of a subroutine
	return $self->maybe_parens_func($name,
				$self->pp_rv2cv($op->first, 16), $cx, 16);
    }
    if ($op->flags & OPf_SPECIAL) {
	# Array element, not hash element
	return $self->maybe_parens_func($name,
				$self->pp_aelem($op->first, 16), $cx, 16);
    }
    return $self->maybe_parens_func($name, $self->pp_helem($op->first, 16),
				    $cx, 16);
}

sub pp_delete {
    my $self = shift;
    my($op, $cx) = @_;
    my $arg;
    my $name = $self->keyword("delete");
    if ($op->private & OPpSLICE) {
	if ($op->flags & OPf_SPECIAL) {
	    # Deleting from an array, not a hash
	    return $self->maybe_parens_func($name,
					$self->pp_aslice($op->first, 16),
					$cx, 16);
	}
	return $self->maybe_parens_func($name,
					$self->pp_hslice($op->first, 16),
					$cx, 16);
    } else {
	if ($op->flags & OPf_SPECIAL) {
	    # Deleting from an array, not a hash
	    return $self->maybe_parens_func($name,
					$self->pp_aelem($op->first, 16),
					$cx, 16);
	}
	return $self->maybe_parens_func($name,
					$self->pp_helem($op->first, 16),
					$cx, 16);
    }
}

sub pp_require {
    my $self = shift;
    my($op, $cx) = @_;
    my $opname = $op->flags & OPf_SPECIAL ? 'CORE::require' : 'require';
    my $kid = $op->first;
    if ($kid->name eq 'const') {
	my $priv = $kid->private;
	my $sv = $self->const_sv($kid);
	my $arg;
	if ($priv & OPpCONST_BARE) {
	    $arg = $sv->PV;
	    $arg =~ s[/][::]g;
	    $arg =~ s/\.pm//g;
	} elsif ($priv & OPpCONST_NOVER) {
	    $opname = $self->keyword('no');
	    $arg = $self->const($sv, 16);
	} elsif ((my $tmp = $self->const($sv, 16)) =~ /^v/) {
	    $arg = $tmp;
	}
	if ($arg) {
	    return $self->maybe_parens("$opname $arg", $cx, 16);
	}
    }
    $self->unop(
	    $op, $cx,
	    $opname,
	    1, # llafr does not apply
    );
}

sub pp_scalar {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first;
    if (not null $kid->sibling) {
	# XXX Was a here-doc
	return $self->dquote($op);
    }
    $self->unop(@_, "scalar");
}


sub padval {
    my $self = shift;
    my $targ = shift;
    return $self->{'curcv'}->PADLIST->ARRAYelt(1)->ARRAYelt($targ);
}

sub anon_hash_or_list {
    my $self = shift;
    my($op, $cx) = @_;

    my($pre, $post) = @{{"anonlist" => ["[","]"],
			 "anonhash" => ["{","}"]}->{$op->name}};
    my($expr, @exprs);
    $op = $op->first->sibling; # skip pushmark
    for (; !null($op); $op = $op->sibling) {
	$expr = $self->deparse($op, 6);
	push @exprs, $expr;
    }
    if ($pre eq "{" and $cx < 1) {
	# Disambiguate that it's not a block
	$pre = "+{";
    }
    return $pre . join(", ", @exprs) . $post;
}

sub pp_anonlist {
    my $self = shift;
    my ($op, $cx) = @_;
    if ($op->flags & OPf_SPECIAL) {
	return $self->anon_hash_or_list($op, $cx);
    }
    warn "Unexpected op pp_" . $op->name() . " without OPf_SPECIAL";
    return 'XXX';
}

*pp_anonhash = \&pp_anonlist;

sub pp_refgen {
    my $self = shift;	
    my($op, $cx) = @_;
    my $kid = $op->first;
    if ($kid->name eq "null") {
	my $anoncode = $kid = $kid->first;
	if ($anoncode->name eq "anonconst") {
	    $anoncode = $anoncode->first->first->sibling;
	}
	if ($anoncode->name eq "anoncode"
	 or !null($anoncode = $kid->sibling) and
		 $anoncode->name eq "anoncode") {
            return $self->e_anoncode({ code => $self->padval($anoncode->targ) });
	} elsif ($kid->name eq "pushmark") {
            my $sib_name = $kid->sibling->name;
            if ($sib_name eq 'entersub') {
                my $text = $self->deparse($kid->sibling, 1);
                # Always show parens for \(&func()), but only with -p otherwise
                $text = "($text)" if $self->{'parens'}
                                 or $kid->sibling->private & OPpENTERSUB_AMPER;
                return "\\$text";
            }
        }
    }
    local $self->{'in_refgen'} = 1;
    $self->pfixop($op, $cx, "\\", 20);
}

sub e_anoncode {
    my ($self, $info) = @_;
    my $text = $self->deparse_sub($info->{code});
    return $self->keyword("sub") . " $text";
}

sub pp_srefgen { pp_refgen(@_) }

sub pp_readline {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first;
    if (is_scalar($kid)
        and $op->flags & OPf_SPECIAL
        and $self->deparse($kid, 1) eq 'ARGV')
    {
        return '<<>>';
    }
    return $self->unop($op, $cx, "readline");
}

sub pp_rcatline {
    my $self = shift;
    my($op) = @_;
    return "<" . $self->gv_name($self->gv_or_padgv($op)) . ">";
}

# Unary operators that can occur as pseudo-listops inside double quotes
sub dq_unop {
    my $self = shift;
    my($op, $cx, $name, $prec, $flags) = (@_, 0, 0);
    my $kid;
    if ($op->flags & OPf_KIDS) {
       $kid = $op->first;
       # If there's more than one kid, the first is an ex-pushmark.
       $kid = $kid->sibling if not null $kid->sibling;
       return $self->maybe_parens_unop($name, $kid, $cx);
    } else {
       return $name .  ($op->flags & OPf_SPECIAL ? "()" : "");
    }
}

sub pp_ucfirst { dq_unop(@_, "ucfirst") }
sub pp_lcfirst { dq_unop(@_, "lcfirst") }
sub pp_uc { dq_unop(@_, "uc") }
sub pp_lc { dq_unop(@_, "lc") }
sub pp_quotemeta { maybe_targmy(@_, \&dq_unop, "quotemeta") }
sub pp_fc { dq_unop(@_, "fc") }

sub loopex {
    my $self = shift;
    my ($op, $cx, $name) = @_;
    if (class($op) eq "PVOP") {
	$name .= " " . $op->pv;
    } elsif (class($op) eq "OP") {
	# no-op
    } elsif (class($op) eq "UNOP") {
	(my $kid = $self->deparse($op->first, 7)) =~ s/^\cS//;
	# last foo() is a syntax error.
	$kid =~ /^(?!\d)\w/ and $kid = "($kid)";
	$name .= " $kid";
    }
    return $self->maybe_parens($name, $cx, 7);
}

sub pp_last { loopex(@_, "last") }
sub pp_next { loopex(@_, "next") }
sub pp_redo { loopex(@_, "redo") }
sub pp_goto { loopex(@_, "goto") }
sub pp_dump { loopex(@_, "CORE::dump") }

sub ftst {
    my $self = shift;
    my($op, $cx, $name) = @_;
    if (class($op) eq "UNOP") {
	# Genuine '-X' filetests are exempt from the LLAFR, but not
	# l?stat()
	if ($name =~ /^-/) {
	    (my $kid = $self->deparse($op->first, 16)) =~ s/^\cS//;
	    return $self->maybe_parens("$name $kid", $cx, 16);
	}
	return $self->maybe_parens_unop($name, $op->first, $cx);
    } elsif (class($op) =~ /^(SV|PAD)OP$/) {
	return $self->maybe_parens_func($name, $self->pp_gv($op, 1), $cx, 16);
    } else { # I don't think baseop filetests ever survive ck_ftst, but...
	return $name;
    }
}

sub pp_lstat    { ftst(@_, "lstat") }
sub pp_stat     { ftst(@_, "stat") }
sub pp_ftrread  { ftst(@_, "-R") }
sub pp_ftrwrite { ftst(@_, "-W") }
sub pp_ftrexec  { ftst(@_, "-X") }
sub pp_fteread  { ftst(@_, "-r") }
sub pp_ftewrite { ftst(@_, "-w") }
sub pp_fteexec  { ftst(@_, "-x") }
sub pp_ftis     { ftst(@_, "-e") }
sub pp_fteowned { ftst(@_, "-O") }
sub pp_ftrowned { ftst(@_, "-o") }
sub pp_ftzero   { ftst(@_, "-z") }
sub pp_ftsize   { ftst(@_, "-s") }
sub pp_ftmtime  { ftst(@_, "-M") }
sub pp_ftatime  { ftst(@_, "-A") }
sub pp_ftctime  { ftst(@_, "-C") }
sub pp_ftsock   { ftst(@_, "-S") }
sub pp_ftchr    { ftst(@_, "-c") }
sub pp_ftblk    { ftst(@_, "-b") }
sub pp_ftfile   { ftst(@_, "-f") }
sub pp_ftdir    { ftst(@_, "-d") }
sub pp_ftpipe   { ftst(@_, "-p") }
sub pp_ftlink   { ftst(@_, "-l") }
sub pp_ftsuid   { ftst(@_, "-u") }
sub pp_ftsgid   { ftst(@_, "-g") }
sub pp_ftsvtx   { ftst(@_, "-k") }
sub pp_fttty    { ftst(@_, "-t") }
sub pp_fttext   { ftst(@_, "-T") }
sub pp_ftbinary { ftst(@_, "-B") }

sub SWAP_CHILDREN () { 1 }
sub ASSIGN () { 2 } # has OP= variant
sub LIST_CONTEXT () { 4 } # Assignment is in list context

my(%left, %right);

sub assoc_class {
    my $op = shift;
    my $name = $op->name;
    if ($name eq "concat" and $op->first->name eq "concat") {
	# avoid spurious '=' -- see comment in pp_concat
	return "concat";
    }
    if ($name eq "null" and class($op) eq "UNOP"
	and $op->first->name =~ /^(and|x?or)$/
	and null $op->first->sibling)
    {
	# Like all conditional constructs, OP_ANDs and OP_ORs are topped
	# with a null that's used as the common end point of the two
	# flows of control. For precedence purposes, ignore it.
	# (COND_EXPRs have these too, but we don't bother with
	# their associativity).
	return assoc_class($op->first);
    }
    return $name . ($op->flags & OPf_STACKED ? "=" : "");
}

# Left associative operators, like '+', for which
# $a + $b + $c is equivalent to ($a + $b) + $c

BEGIN {
    %left = ('multiply' => 19, 'i_multiply' => 19,
	     'divide' => 19, 'i_divide' => 19,
	     'modulo' => 19, 'i_modulo' => 19,
	     'repeat' => 19,
	     'add' => 18, 'i_add' => 18,
	     'subtract' => 18, 'i_subtract' => 18,
	     'concat' => 18,
	     'left_shift' => 17, 'right_shift' => 17,
	     'bit_and' => 13, 'nbit_and' => 13, 'sbit_and' => 13,
	     'bit_or' => 12, 'bit_xor' => 12,
	     'sbit_or' => 12, 'sbit_xor' => 12,
	     'nbit_or' => 12, 'nbit_xor' => 12,
	     'and' => 3,
	     'or' => 2, 'xor' => 2,
	    );
}

sub deparse_binop_left {
    my $self = shift;
    my($op, $left, $prec) = @_;
    if ($left{assoc_class($op)} && $left{assoc_class($left)}
	and $left{assoc_class($op)} == $left{assoc_class($left)})
    {
	return $self->deparse($left, $prec - .00001);
    } else {
	return $self->deparse($left, $prec);	
    }
}

# Right associative operators, like '=', for which
# $a = $b = $c is equivalent to $a = ($b = $c)

BEGIN {
    %right = ('pow' => 22,
	      'sassign=' => 7, 'aassign=' => 7,
	      'multiply=' => 7, 'i_multiply=' => 7,
	      'divide=' => 7, 'i_divide=' => 7,
	      'modulo=' => 7, 'i_modulo=' => 7,
	      'repeat=' => 7, 'refassign' => 7, 'refassign=' => 7,
	      'add=' => 7, 'i_add=' => 7,
	      'subtract=' => 7, 'i_subtract=' => 7,
	      'concat=' => 7,
	      'left_shift=' => 7, 'right_shift=' => 7,
	      'bit_and=' => 7, 'sbit_and=' => 7, 'nbit_and=' => 7,
	      'nbit_or=' => 7, 'nbit_xor=' => 7,
	      'sbit_or=' => 7, 'sbit_xor=' => 7,
	      'andassign' => 7,
	      'orassign' => 7,
	     );
}

sub deparse_binop_right {
    my $self = shift;
    my($op, $right, $prec) = @_;
    if ($right{assoc_class($op)} && $right{assoc_class($right)}
	and $right{assoc_class($op)} == $right{assoc_class($right)})
    {
	return $self->deparse($right, $prec - .00001);
    } else {
	return $self->deparse($right, $prec);	
    }
}

sub binop {
    my $self = shift;
    my ($op, $cx, $opname, $prec, $flags) = (@_, 0);
    my $left = $op->first;
    my $right = $op->last;
    my $eq = "";
    if ($op->flags & OPf_STACKED && $flags & ASSIGN) {
	$eq = "=";
	$prec = 7;
    }
    if ($flags & SWAP_CHILDREN) {
	($left, $right) = ($right, $left);
    }
    my $leftop = $left;
    $left = $self->deparse_binop_left($op, $left, $prec);
    $left = "($left)" if $flags & LIST_CONTEXT
		     and    $left !~ /^(my|our|local|)[\@\(]/
			 || do {
				# Parenthesize if the left argument is a
				# lone repeat op.
				my $left = $leftop->first->sibling;
				$left->name eq 'repeat'
				    && null($left->sibling);
			    };
    $right = $self->deparse_binop_right($op, $right, $prec);
    return $self->maybe_parens("$left $opname$eq $right", $cx, $prec);
}

sub pp_add { maybe_targmy(@_, \&binop, "+", 18, ASSIGN) }
sub pp_multiply { maybe_targmy(@_, \&binop, "*", 19, ASSIGN) }
sub pp_subtract { maybe_targmy(@_, \&binop, "-",18,  ASSIGN) }
sub pp_divide { maybe_targmy(@_, \&binop, "/", 19, ASSIGN) }
sub pp_modulo { maybe_targmy(@_, \&binop, "%", 19, ASSIGN) }
sub pp_i_add { maybe_targmy(@_, \&binop, "+", 18, ASSIGN) }
sub pp_i_multiply { maybe_targmy(@_, \&binop, "*", 19, ASSIGN) }
sub pp_i_subtract { maybe_targmy(@_, \&binop, "-", 18, ASSIGN) }
sub pp_i_divide { maybe_targmy(@_, \&binop, "/", 19, ASSIGN) }
sub pp_i_modulo { maybe_targmy(@_, \&binop, "%", 19, ASSIGN) }
sub pp_pow { maybe_targmy(@_, \&binop, "**", 22, ASSIGN) }

sub pp_left_shift { maybe_targmy(@_, \&binop, "<<", 17, ASSIGN) }
sub pp_right_shift { maybe_targmy(@_, \&binop, ">>", 17, ASSIGN) }
sub pp_bit_and { maybe_targmy(@_, \&binop, "&", 13, ASSIGN) }
sub pp_bit_or { maybe_targmy(@_, \&binop, "|", 12, ASSIGN) }
sub pp_bit_xor { maybe_targmy(@_, \&binop, "^", 12, ASSIGN) }
*pp_nbit_and = *pp_bit_and;
*pp_nbit_or  = *pp_bit_or;
*pp_nbit_xor = *pp_bit_xor;
sub pp_sbit_and { maybe_targmy(@_, \&binop, "&.", 13, ASSIGN) }
sub pp_sbit_or { maybe_targmy(@_, \&binop, "|.", 12, ASSIGN) }
sub pp_sbit_xor { maybe_targmy(@_, \&binop, "^.", 12, ASSIGN) }

sub pp_eq { binop(@_, "==", 14) }
sub pp_ne { binop(@_, "!=", 14) }
sub pp_lt { binop(@_, "<", 15) }
sub pp_gt { binop(@_, ">", 15) }
sub pp_ge { binop(@_, ">=", 15) }
sub pp_le { binop(@_, "<=", 15) }
sub pp_ncmp { binop(@_, "<=>", 14) }
sub pp_i_eq { binop(@_, "==", 14) }
sub pp_i_ne { binop(@_, "!=", 14) }
sub pp_i_lt { binop(@_, "<", 15) }
sub pp_i_gt { binop(@_, ">", 15) }
sub pp_i_ge { binop(@_, ">=", 15) }
sub pp_i_le { binop(@_, "<=", 15) }
sub pp_i_ncmp { maybe_targmy(@_, \&binop, "<=>", 14) }

sub pp_seq { binop(@_, "eq", 14) }
sub pp_sne { binop(@_, "ne", 14) }
sub pp_slt { binop(@_, "lt", 15) }
sub pp_sgt { binop(@_, "gt", 15) }
sub pp_sge { binop(@_, "ge", 15) }
sub pp_sle { binop(@_, "le", 15) }
sub pp_scmp { maybe_targmy(@_, \&binop, "cmp", 14) }

sub pp_sassign { binop(@_, "=", 7, SWAP_CHILDREN) }
sub pp_aassign { binop(@_, "=", 7, SWAP_CHILDREN | LIST_CONTEXT) }

sub pp_smartmatch {
    my ($self, $op, $cx) = @_;
    if ($op->flags & OPf_SPECIAL) {
	return $self->deparse($op->last, $cx);
    }
    else {
	binop(@_, "~~", 14);
    }
}

# '.' is special because concats-of-concats are optimized to save copying
# by making all but the first concat stacked. The effect is as if the
# programmer had written '($a . $b) .= $c', except legal.
sub pp_concat { maybe_targmy(@_, \&real_concat) }
sub real_concat {
    my $self = shift;
    my($op, $cx) = @_;
    my $left = $op->first;
    my $right = $op->last;
    my $eq = "";
    my $prec = 18;
    if ($op->flags & OPf_STACKED and $op->first->name ne "concat") {
	$eq = "=";
	$prec = 7;
    }
    $left = $self->deparse_binop_left($op, $left, $prec);
    $right = $self->deparse_binop_right($op, $right, $prec);
    return $self->maybe_parens("$left .$eq $right", $cx, $prec);
}

sub pp_repeat { maybe_targmy(@_, \&repeat) }

# 'x' is weird when the left arg is a list
sub repeat {
    my $self = shift;
    my($op, $cx) = @_;
    my $left = $op->first;
    my $right = $op->last;
    my $eq = "";
    my $prec = 19;
    if ($op->flags & OPf_STACKED) {
	$eq = "=";
	$prec = 7;
    }
    if (null($right)) { # list repeat; count is inside left-side ex-list
			# in 5.21.5 and earlier
	my $kid = $left->first->sibling; # skip pushmark
	my @exprs;
	for (; !null($kid->sibling); $kid = $kid->sibling) {
	    push @exprs, $self->deparse($kid, 6);
	}
	$right = $kid;
	$left = "(" . join(", ", @exprs). ")";
    } else {
	my $dolist = $op->private & OPpREPEAT_DOLIST;
	$left = $self->deparse_binop_left($op, $left, $dolist ? 1 : $prec);
	if ($dolist) {
	    $left = "($left)";
	}
    }
    $right = $self->deparse_binop_right($op, $right, $prec);
    return $self->maybe_parens("$left x$eq $right", $cx, $prec);
}

sub range {
    my $self = shift;
    my ($op, $cx, $type) = @_;
    my $left = $op->first;
    my $right = $left->sibling;
    $left = $self->deparse($left, 9);
    $right = $self->deparse($right, 9);
    return $self->maybe_parens("$left $type $right", $cx, 9);
}

sub pp_flop {
    my $self = shift;
    my($op, $cx) = @_;
    my $flip = $op->first;
    my $type = ($flip->flags & OPf_SPECIAL) ? "..." : "..";
    return $self->range($flip->first, $cx, $type);
}

# one-line while/until is handled in pp_leave

sub logop {
    my $self = shift;
    my ($op, $cx, $lowop, $lowprec, $highop, $highprec, $blockname) = @_;
    my $left = $op->first;
    my $right = $op->first->sibling;
    $blockname &&= $self->keyword($blockname);
    if ($cx < 1 and is_scope($right) and $blockname
	and $self->{'expand'} < 7)
    { # if ($a) {$b}
	$left = $self->deparse($left, 1);
	$right = $self->deparse($right, 0);
	return "$blockname ($left) {\n\t$right\n\b}\cK";
    } elsif ($cx < 1 and $blockname and not $self->{'parens'}
	     and $self->{'expand'} < 7) { # $b if $a
	$right = $self->deparse($right, 1);
	$left = $self->deparse($left, 1);
	return "$right $blockname $left";
    } elsif ($cx > $lowprec and $highop) { # $a && $b
	$left = $self->deparse_binop_left($op, $left, $highprec);
	$right = $self->deparse_binop_right($op, $right, $highprec);
	return $self->maybe_parens("$left $highop $right", $cx, $highprec);
    } else { # $a and $b
	$left = $self->deparse_binop_left($op, $left, $lowprec);
	$right = $self->deparse_binop_right($op, $right, $lowprec);
	return $self->maybe_parens("$left $lowop $right", $cx, $lowprec);
    }
}

sub pp_and { logop(@_, "and", 3, "&&", 11, "if") }
sub pp_or  { logop(@_, "or",  2, "||", 10, "unless") }
sub pp_dor { logop(@_, "//", 10) }

# xor is syntactically a logop, but it's really a binop (contrary to
# old versions of opcode.pl). Syntax is what matters here.
sub pp_xor { logop(@_, "xor", 2, "",   0,  "") }

sub logassignop {
    my $self = shift;
    my ($op, $cx, $opname) = @_;
    my $left = $op->first;
    my $right = $op->first->sibling->first; # skip sassign
    $left = $self->deparse($left, 7);
    $right = $self->deparse($right, 7);
    return $self->maybe_parens("$left $opname $right", $cx, 7);
}

sub pp_andassign { logassignop(@_, "&&=") }
sub pp_orassign  { logassignop(@_, "||=") }
sub pp_dorassign { logassignop(@_, "//=") }

sub rv2gv_or_string {
    my($self,$op) = @_;
    if ($op->name eq "gv") { # could be open("open") or open("###")
	my($name,$quoted) =
	    $self->stash_variable_name("", $self->gv_or_padgv($op));
	$quoted ? $name : "*$name";
    }
    else {
	$self->deparse($op, 6);
    }
}

sub listop {
    my $self = shift;
    my($op, $cx, $name, $kid, $nollafr) = @_;
    my(@exprs);
    my $parens = ($cx >= 5) || $self->{'parens'};
    $kid ||= $op->first->sibling;
    # If there are no arguments, add final parentheses (or parenthesize the
    # whole thing if the llafr does not apply) to account for cases like
    # (return)+1 or setpgrp()+1.  When the llafr does not apply, we use a
    # precedence of 6 (< comma), as "return, 1" does not need parentheses.
    if (null $kid) {
	return $nollafr
		? $self->maybe_parens($self->keyword($name), $cx, 7)
		: $self->keyword($name) . '()' x (7 < $cx);
    }
    my $first;
    my $fullname = $self->keyword($name);
    my $proto = prototype("CORE::$name");
    if (
	 (     (defined $proto && $proto =~ /^;?\*/)
	    || $name eq 'select' # select(F) doesn't have a proto
	 )
	 && $kid->name eq "rv2gv"
	 && !($kid->private & OPpLVAL_INTRO)
    ) {
	$first = $self->rv2gv_or_string($kid->first);
    }
    else {
	$first = $self->deparse($kid, 6);
    }
    if ($name eq "chmod" && $first =~ /^\d+$/) {
	$first = sprintf("%#o", $first);
    }
    $first = "+$first"
	if not $parens and not $nollafr and substr($first, 0, 1) eq "(";
    push @exprs, $first;
    $kid = $kid->sibling;
    if (defined $proto && $proto =~ /^\*\*/ && $kid->name eq "rv2gv"
	 && !($kid->private & OPpLVAL_INTRO)) {
	push @exprs, $first = $self->rv2gv_or_string($kid->first);
	$kid = $kid->sibling;
    }
    for (; !null($kid); $kid = $kid->sibling) {
	push @exprs, $self->deparse($kid, 6);
    }
    if ($name eq "reverse" && ($op->private & OPpREVERSE_INPLACE)) {
	return "$exprs[0] = $fullname"
	         . ($parens ? "($exprs[0])" : " $exprs[0]");
    }

    if ($parens && $nollafr) {
	return "($fullname " . join(", ", @exprs) . ")";
    } elsif ($parens) {
	return "$fullname(" . join(", ", @exprs) . ")";
    } else {
	return "$fullname " . join(", ", @exprs);
    }
}

sub pp_bless { listop(@_, "bless") }
sub pp_atan2 { maybe_targmy(@_, \&listop, "atan2") }
sub pp_substr {
    my ($self,$op,$cx) = @_;
    if ($op->private & OPpSUBSTR_REPL_FIRST) {
	return
	   listop($self, $op, 7, "substr", $op->first->sibling->sibling)
	 . " = "
	 . $self->deparse($op->first->sibling, 7);
    }
    maybe_local(@_, listop(@_, "substr"))
}
sub pp_vec { maybe_targmy(@_, \&maybe_local, listop(@_, "vec")) }
sub pp_index { maybe_targmy(@_, \&listop, "index") }
sub pp_rindex { maybe_targmy(@_, \&listop, "rindex") }
sub pp_sprintf { maybe_targmy(@_, \&listop, "sprintf") }
sub pp_formline { listop(@_, "formline") } # see also deparse_format
sub pp_crypt { maybe_targmy(@_, \&listop, "crypt") }
sub pp_unpack { listop(@_, "unpack") }
sub pp_pack { listop(@_, "pack") }
sub pp_join { maybe_targmy(@_, \&listop, "join") }
sub pp_splice { listop(@_, "splice") }
sub pp_push { maybe_targmy(@_, \&listop, "push") }
sub pp_unshift { maybe_targmy(@_, \&listop, "unshift") }
sub pp_reverse { listop(@_, "reverse") }
sub pp_warn { listop(@_, "warn") }
sub pp_die { listop(@_, "die") }
sub pp_return { listop(@_, "return", undef, 1) } # llafr does not apply
sub pp_open { listop(@_, "open") }
sub pp_pipe_op { listop(@_, "pipe") }
sub pp_tie { listop(@_, "tie") }
sub pp_binmode { listop(@_, "binmode") }
sub pp_dbmopen { listop(@_, "dbmopen") }
sub pp_sselect { listop(@_, "select") }
sub pp_select { listop(@_, "select") }
sub pp_read { listop(@_, "read") }
sub pp_sysopen { listop(@_, "sysopen") }
sub pp_sysseek { listop(@_, "sysseek") }
sub pp_sysread { listop(@_, "sysread") }
sub pp_syswrite { listop(@_, "syswrite") }
sub pp_send { listop(@_, "send") }
sub pp_recv { listop(@_, "recv") }
sub pp_seek { listop(@_, "seek") }
sub pp_fcntl { listop(@_, "fcntl") }
sub pp_ioctl { listop(@_, "ioctl") }
sub pp_flock { maybe_targmy(@_, \&listop, "flock") }
sub pp_socket { listop(@_, "socket") }
sub pp_sockpair { listop(@_, "socketpair") }
sub pp_bind { listop(@_, "bind") }
sub pp_connect { listop(@_, "connect") }
sub pp_listen { listop(@_, "listen") }
sub pp_accept { listop(@_, "accept") }
sub pp_shutdown { listop(@_, "shutdown") }
sub pp_gsockopt { listop(@_, "getsockopt") }
sub pp_ssockopt { listop(@_, "setsockopt") }
sub pp_chown { maybe_targmy(@_, \&listop, "chown") }
sub pp_unlink { maybe_targmy(@_, \&listop, "unlink") }
sub pp_chmod { maybe_targmy(@_, \&listop, "chmod") }
sub pp_utime { maybe_targmy(@_, \&listop, "utime") }
sub pp_rename { maybe_targmy(@_, \&listop, "rename") }
sub pp_link { maybe_targmy(@_, \&listop, "link") }
sub pp_symlink { maybe_targmy(@_, \&listop, "symlink") }
sub pp_mkdir { maybe_targmy(@_, \&listop, "mkdir") }
sub pp_open_dir { listop(@_, "opendir") }
sub pp_seekdir { listop(@_, "seekdir") }
sub pp_waitpid { maybe_targmy(@_, \&listop, "waitpid") }
sub pp_system { maybe_targmy(@_, \&indirop, "system") }
sub pp_exec { maybe_targmy(@_, \&indirop, "exec") }
sub pp_kill { maybe_targmy(@_, \&listop, "kill") }
sub pp_setpgrp { maybe_targmy(@_, \&listop, "setpgrp") }
sub pp_getpriority { maybe_targmy(@_, \&listop, "getpriority") }
sub pp_setpriority { maybe_targmy(@_, \&listop, "setpriority") }
sub pp_shmget { listop(@_, "shmget") }
sub pp_shmctl { listop(@_, "shmctl") }
sub pp_shmread { listop(@_, "shmread") }
sub pp_shmwrite { listop(@_, "shmwrite") }
sub pp_msgget { listop(@_, "msgget") }
sub pp_msgctl { listop(@_, "msgctl") }
sub pp_msgsnd { listop(@_, "msgsnd") }
sub pp_msgrcv { listop(@_, "msgrcv") }
sub pp_semget { listop(@_, "semget") }
sub pp_semctl { listop(@_, "semctl") }
sub pp_semop { listop(@_, "semop") }
sub pp_ghbyaddr { listop(@_, "gethostbyaddr") }
sub pp_gnbyaddr { listop(@_, "getnetbyaddr") }
sub pp_gpbynumber { listop(@_, "getprotobynumber") }
sub pp_gsbyname { listop(@_, "getservbyname") }
sub pp_gsbyport { listop(@_, "getservbyport") }
sub pp_syscall { listop(@_, "syscall") }

sub pp_glob {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first->sibling;  # skip pushmark
    my $keyword =
	$op->flags & OPf_SPECIAL ? 'glob' : $self->keyword('glob');
    my $text = $self->deparse($kid);
    return $cx >= 5 || $self->{'parens'}
	? "$keyword($text)"
	: "$keyword $text";
}

# Truncate is special because OPf_SPECIAL makes a bareword first arg
# be a filehandle. This could probably be better fixed in the core
# by moving the GV lookup into ck_truc.

sub pp_truncate {
    my $self = shift;
    my($op, $cx) = @_;
    my(@exprs);
    my $parens = ($cx >= 5) || $self->{'parens'};
    my $kid = $op->first->sibling;
    my $fh;
    if ($op->flags & OPf_SPECIAL) {
	# $kid is an OP_CONST
	$fh = $self->const_sv($kid)->PV;
    } else {
	$fh = $self->deparse($kid, 6);
        $fh = "+$fh" if not $parens and substr($fh, 0, 1) eq "(";
    }
    my $len = $self->deparse($kid->sibling, 6);
    my $name = $self->keyword('truncate');
    if ($parens) {
	return "$name($fh, $len)";
    } else {
	return "$name $fh, $len";
    }
}

sub indirop {
    my $self = shift;
    my($op, $cx, $name) = @_;
    my($expr, @exprs);
    my $firstkid = my $kid = $op->first->sibling;
    my $indir = "";
    if ($op->flags & OPf_STACKED) {
	$indir = $kid;
	$indir = $indir->first; # skip rv2gv
	if (is_scope($indir)) {
	    $indir = "{" . $self->deparse($indir, 0) . "}";
	    $indir = "{;}" if $indir eq "{}";
	} elsif ($indir->name eq "const" && $indir->private & OPpCONST_BARE) {
	    $indir = $self->const_sv($indir)->PV;
	} else {
	    $indir = $self->deparse($indir, 24);
	}
	$indir = $indir . " ";
	$kid = $kid->sibling;
    }
    if ($name eq "sort" && $op->private & (OPpSORT_NUMERIC | OPpSORT_INTEGER)) {
	$indir = ($op->private & OPpSORT_DESCEND) ? '{$b <=> $a} '
						  : '{$a <=> $b} ';
    }
    elsif ($name eq "sort" && $op->private & OPpSORT_DESCEND) {
	$indir = '{$b cmp $a} ';
    }
    for (; !null($kid); $kid = $kid->sibling) {
	$expr = $self->deparse($kid, !$indir && $kid == $firstkid && $name eq "sort" && $firstkid->name eq "entersub" ? 16 : 6);
	push @exprs, $expr;
    }
    my $name2;
    if ($name eq "sort" && $op->private & OPpSORT_REVERSE) {
	$name2 = $self->keyword('reverse') . ' ' . $self->keyword('sort');
    }
    else { $name2 = $self->keyword($name) }
    if ($name eq "sort" && ($op->private & OPpSORT_INPLACE)) {
	return "$exprs[0] = $name2 $indir $exprs[0]";
    }

    my $args = $indir . join(", ", @exprs);
    if ($indir ne "" && $name eq "sort") {
	# We don't want to say "sort(f 1, 2, 3)", since perl -w will
	# give bareword warnings in that case. Therefore if context
	# requires, we'll put parens around the outside "(sort f 1, 2,
	# 3)". Unfortunately, we'll currently think the parens are
	# necessary more often that they really are, because we don't
	# distinguish which side of an assignment we're on.
	if ($cx >= 5) {
	    return "($name2 $args)";
	} else {
	    return "$name2 $args";
	}
    } elsif (
	!$indir && $name eq "sort"
      && !null($op->first->sibling)
      && $op->first->sibling->name eq 'entersub'
    ) {
	# We cannot say sort foo(bar), as foo will be interpreted as a
	# comparison routine.  We have to say sort(...) in that case.
	return "$name2($args)";
    } else {
	return length $args
		? $self->maybe_parens_func($name2, $args, $cx, 5)
		: $name2 . '()' x (7 < $cx);
    }

}

sub pp_prtf { indirop(@_, "printf") }
sub pp_print { indirop(@_, "print") }
sub pp_say  { indirop(@_, "say") }
sub pp_sort { indirop(@_, "sort") }

sub mapop {
    my $self = shift;
    my($op, $cx, $name) = @_;
    my($expr, @exprs);
    my $kid = $op->first; # this is the (map|grep)start
    $kid = $kid->first->sibling; # skip a pushmark
    my $code = $kid->first; # skip a null
    if (is_scope $code) {
	$code = "{" . $self->deparse($code, 0) . "} ";
    } else {
	$code = $self->deparse($code, 24);
	$code .= ", " if !null($kid->sibling);
    }
    $kid = $kid->sibling;
    for (; !null($kid); $kid = $kid->sibling) {
	$expr = $self->deparse($kid, 6);
	push @exprs, $expr if defined $expr;
    }
    return $self->maybe_parens_func($self->keyword($name),
				    $code . join(", ", @exprs), $cx, 5);
}

sub pp_mapwhile { mapop(@_, "map") }
sub pp_grepwhile { mapop(@_, "grep") }
sub pp_mapstart { baseop(@_, "map") }
sub pp_grepstart { baseop(@_, "grep") }

my %uses_intro;
BEGIN {
    @uses_intro{
	eval { require B::Op_private }
	  ? @{$B::Op_private::ops_using{OPpLVAL_INTRO}}
	  : qw(gvsv rv2sv rv2hv rv2gv rv2av aelem helem aslice
	       hslice delete padsv padav padhv enteriter entersub padrange
	       pushmark cond_expr refassign list)
    } = ();
    delete @uses_intro{qw( lvref lvrefslice lvavref entersub )};
}

sub pp_list {
    my $self = shift;
    my($op, $cx) = @_;
    my($expr, @exprs);
    my $kid = $op->first->sibling; # skip pushmark
    return '' if class($kid) eq 'NULL';
    my $lop;
    my $local = "either"; # could be local(...), my(...), state(...) or our(...)
    my $type;
    for ($lop = $kid; !null($lop); $lop = $lop->sibling) {
	my $lopname = $lop->name;
	my $loppriv = $lop->private;
	my $newtype;
	if ($lopname =~ /^pad[ash]v$/ && $loppriv & OPpLVAL_INTRO) {
	    if ($loppriv & OPpPAD_STATE) { # state()
		($local = "", last) if $local !~ /^(?:either|state)$/;
		$local = "state";
	    } else { # my()
		($local = "", last) if $local !~ /^(?:either|my)$/;
		$local = "my";
	    }
	    my $padname = $self->padname_sv($lop->targ);
	    if ($padname->FLAGS & SVpad_TYPED) {
		$newtype = $padname->SvSTASH->NAME;
	    }
	} elsif ($lopname =~ /^(?:gv|rv2)([ash])v$/
			&& $loppriv & OPpOUR_INTRO
		or $lopname eq "null" && class($lop) eq 'UNOP'
			&& $lop->first->name eq "gvsv"
			&& $lop->first->private & OPpOUR_INTRO) { # our()
	    my $newlocal = "local " x !!($loppriv & OPpLVAL_INTRO) . "our";
	    ($local = "", last)
		if $local ne 'either' && $local ne $newlocal;
	    $local = $newlocal;
	    my $funny = !$1 || $1 eq 's' ? '$' : $1 eq 'a' ? '@' : '%';
	    if (my $t = $self->find_our_type(
		    $funny . $self->gv_or_padgv($lop->first)->NAME
	       )) {
		$newtype = $t;
	    }
	} elsif ($lopname ne 'undef'
	   and    !($loppriv & OPpLVAL_INTRO)
	       || !exists $uses_intro{$lopname eq 'null'
					? substr B::ppname($lop->targ), 3
					: $lopname})
	{
	    $local = ""; # or not
	    last;
	} elsif ($lopname ne "undef")
	{
	    # local()
	    ($local = "", last) if $local !~ /^(?:either|local)$/;
	    $local = "local";
	}
	if (defined $type && defined $newtype && $newtype ne $type) {
	    $local = '';
	    last;
	}
	$type = $newtype;
    }
    $local = "" if $local eq "either"; # no point if it's all undefs
    $local &&= join ' ', map $self->keyword($_), split / /, $local;
    $local .= " $type " if $local && length $type;
    return $self->deparse($kid, $cx) if null $kid->sibling and not $local;
    for (; !null($kid); $kid = $kid->sibling) {
	if ($local) {
	    if (class($kid) eq "UNOP" and $kid->first->name eq "gvsv") {
		$lop = $kid->first;
	    } else {
		$lop = $kid;
	    }
	    $self->{'avoid_local'}{$$lop}++;
	    $expr = $self->deparse($kid, 6);
	    delete $self->{'avoid_local'}{$$lop};
	} else {
	    $expr = $self->deparse($kid, 6);
	}
	push @exprs, $expr;
    }
    if ($local) {
	return "$local(" . join(", ", @exprs) . ")";
    } else {
	return $self->maybe_parens( join(", ", @exprs), $cx, 6);	
    }
}

sub is_ifelse_cont {
    my $op = shift;
    return ($op->name eq "null" and class($op) eq "UNOP"
	    and $op->first->name =~ /^(and|cond_expr)$/
	    and is_scope($op->first->first->sibling));
}

sub pp_cond_expr {
    my $self = shift;
    my($op, $cx) = @_;
    my $cond = $op->first;
    my $true = $cond->sibling;
    my $false = $true->sibling;
    my $cuddle = $self->{'cuddle'};
    unless ($cx < 1 and (is_scope($true) and $true->name ne "null") and
	    (is_scope($false) || is_ifelse_cont($false))
	    and $self->{'expand'} < 7) {
	$cond = $self->deparse($cond, 8);
	$true = $self->deparse($true, 6);
	$false = $self->deparse($false, 8);
	return $self->maybe_parens("$cond ? $true : $false", $cx, 8);
    }

    $cond = $self->deparse($cond, 1);
    $true = $self->deparse($true, 0);
    my $head = $self->keyword("if") . " ($cond) {\n\t$true\n\b}";
    my @elsifs;
    my $elsif;
    while (!null($false) and is_ifelse_cont($false)) {
	my $newop = $false->first;
	my $newcond = $newop->first;
	my $newtrue = $newcond->sibling;
	$false = $newtrue->sibling; # last in chain is OP_AND => no else
	if ($newcond->name eq "lineseq")
	{
	    # lineseq to ensure correct line numbers in elsif()
	    # Bug #37302 fixed by change #33710.
	    $newcond = $newcond->first->sibling;
	}
	$newcond = $self->deparse($newcond, 1);
	$newtrue = $self->deparse($newtrue, 0);
	$elsif ||= $self->keyword("elsif");
	push @elsifs, "$elsif ($newcond) {\n\t$newtrue\n\b}";
    }
    if (!null($false)) {
	$false = $cuddle . $self->keyword("else") . " {\n\t" .
	  $self->deparse($false, 0) . "\n\b}\cK";
    } else {
	$false = "\cK";
    }
    return $head . join($cuddle, "", @elsifs) . $false;
}

sub pp_once {
    my ($self, $op, $cx) = @_;
    my $cond = $op->first;
    my $true = $cond->sibling;

    my $ret = $self->deparse($true, $cx);
    $ret =~ s/^(\(?)\$/$1 . $self->keyword("state") . ' $'/e;
    $ret;
}

sub loop_common {
    my $self = shift;
    my($op, $cx, $init) = @_;
    my $enter = $op->first;
    my $kid = $enter->sibling;
    local(@$self{qw'curstash warnings hints hinthash'})
		= @$self{qw'curstash warnings hints hinthash'};
    my $head = "";
    my $bare = 0;
    my $body;
    my $cond = undef;
    my $name;
    if ($kid->name eq "lineseq") { # bare or infinite loop
	if ($kid->last->name eq "unstack") { # infinite
	    $head = "while (1) "; # Can't use for(;;) if there's a continue
	    $cond = "";
	} else {
	    $bare = 1;
	}
	$body = $kid;
    } elsif ($enter->name eq "enteriter") { # foreach
	my $ary = $enter->first->sibling; # first was pushmark
	my $var = $ary->sibling;
	if ($ary->name eq 'null' and $enter->private & OPpITER_REVERSED) {
	    # "reverse" was optimised away
	    $ary = listop($self, $ary->first->sibling, 1, 'reverse');
	} elsif ($enter->flags & OPf_STACKED
	    and not null $ary->first->sibling->sibling)
	{
	    $ary = $self->deparse($ary->first->sibling, 9) . " .. " .
	      $self->deparse($ary->first->sibling->sibling, 9);
	} else {
	    $ary = $self->deparse($ary, 1);
	}
	if (null $var) {
            $var = $self->pp_padsv($enter, 1, 1);
	} elsif ($var->name eq "rv2gv") {
	    $var = $self->pp_rv2sv($var, 1);
	    if ($enter->private & OPpOUR_INTRO) {
		# our declarations don't have package names
		$var =~ s/^(.).*::/$1/;
		$var = "our $var";
	    }
	} elsif ($var->name eq "gv") {
	    $var = "\$" . $self->deparse($var, 1);
	} else {
	    $var = $self->deparse($var, 1);
	}
	$body = $kid->first->first->sibling; # skip OP_AND and OP_ITER
	if (!is_state $body->first and $body->first->name !~ /^(?:stub|leave|scope)$/) {
	    confess unless $var eq '$_';
	    $body = $body->first;
	    return $self->deparse($body, 2) . " "
		 . $self->keyword("foreach") . " ($ary)";
	}
	$head = "foreach $var ($ary) ";
    } elsif ($kid->name eq "null") { # while/until
	$kid = $kid->first;
	$name = {"and" => "while", "or" => "until"}->{$kid->name};
	$cond = $kid->first;
	$body = $kid->first->sibling;
    } elsif ($kid->name eq "stub") { # bare and empty
	return "{;}"; # {} could be a hashref
    }
    # If there isn't a continue block, then the next pointer for the loop
    # will point to the unstack, which is kid's last child, except
    # in a bare loop, when it will point to the leaveloop. When neither of
    # these conditions hold, then the second-to-last child is the continue
    # block (or the last in a bare loop).
    my $cont_start = $enter->nextop;
    my $cont;
    my $precond;
    my $postcond;
    if ($$cont_start != $$op && ${$cont_start} != ${$body->last}) {
	if ($bare) {
	    $cont = $body->last;
	} else {
	    $cont = $body->first;
	    while (!null($cont->sibling->sibling)) {
		$cont = $cont->sibling;
	    }
	}
	my $state = $body->first;
	my $cuddle = $self->{'cuddle'};
	my @states;
	for (; $$state != $$cont; $state = $state->sibling) {
	    push @states, $state;
	}
	$body = $self->lineseq(undef, 0, @states);
	if (defined $cond and not is_scope $cont and $self->{'expand'} < 3) {
	    $precond = "for ($init; ";
	    $postcond = "; " . $self->deparse($cont, 1) .") ";
	    $cont = "\cK";
	} else {
	    $cont = $cuddle . "continue {\n\t" .
	      $self->deparse($cont, 0) . "\n\b}\cK";
	}
    } else {
	return "" if !defined $body;
	if (length $init) {
	    $precond = "for ($init; ";
	    $postcond = ";) ";
	}
	$cont = "\cK";
	$body = $self->deparse($body, 0);
    }
    if ($precond) { # for(;;)
	$cond &&= $name eq 'until'
		    ? listop($self, undef, 1, "not", $cond->first)
		    : $self->deparse($cond, 1);
	$head = "$precond$cond$postcond";
    }
    if ($name && !$head) {
	ref $cond and $cond = $self->deparse($cond, 1);
	$head = "$name ($cond) ";
    }
    $head =~ s/^(for(?:each)?|while|until)/$self->keyword($1)/e;
    $body =~ s/;?$/;\n/;

    return $head . "{\n\t" . $body . "\b}" . $cont;
}

sub pp_leaveloop { shift->loop_common(@_, "") }

sub for_loop {
    my $self = shift;
    my($op, $cx) = @_;
    my $init = $self->deparse($op, 1);
    my $s = $op->sibling;
    my $ll = $s->name eq "unstack" ? $s->sibling : $s->first->sibling;
    return $self->loop_common($ll, $cx, $init);
}

sub pp_leavetry {
    my $self = shift;
    return "eval {\n\t" . $self->pp_leave(@_) . "\n\b}";
}

sub _op_is_or_was {
  my ($op, $expect_type) = @_;
  my $type = $op->type;
  return($type == $expect_type
         || ($type == OP_NULL && $op->targ == $expect_type));
}

sub pp_null {
    my($self, $op, $cx) = @_;
    if (class($op) eq "OP") {
	# old value is lost
	return $self->{'ex_const'} if $op->targ == OP_CONST;
    } elsif (class ($op) eq "COP") {
	    return &pp_nextstate;
    } elsif ($op->first->name eq 'pushmark'
             or $op->first->name eq 'null'
                && $op->first->targ == OP_PUSHMARK
                && _op_is_or_was($op, OP_LIST)) {
	return $self->pp_list($op, $cx);
    } elsif ($op->first->name eq "enter") {
	return $self->pp_leave($op, $cx);
    } elsif ($op->first->name eq "leave") {
	return $self->pp_leave($op->first, $cx);
    } elsif ($op->first->name eq "scope") {
	return $self->pp_scope($op->first, $cx);
    } elsif ($op->targ == OP_STRINGIFY) {
	return $self->dquote($op, $cx);
    } elsif ($op->targ == OP_GLOB) {
	return $self->pp_glob(
	         $op->first    # entersub
	            ->first    # ex-list
	            ->first    # pushmark
	            ->sibling, # glob
	         $cx
	       );
    } elsif (!null($op->first->sibling) and
	     $op->first->sibling->name eq "readline" and
	     $op->first->sibling->flags & OPf_STACKED) {
	return $self->maybe_parens($self->deparse($op->first, 7) . " = "
				   . $self->deparse($op->first->sibling, 7),
				   $cx, 7);
    } elsif (!null($op->first->sibling) and
	     $op->first->sibling->name =~ /^transr?\z/ and
	     $op->first->sibling->flags & OPf_STACKED) {
	return $self->maybe_parens($self->deparse($op->first, 20) . " =~ "
				   . $self->deparse($op->first->sibling, 20),
				   $cx, 20);
    } elsif ($op->flags & OPf_SPECIAL && $cx < 1 && !$op->targ) {
	return ($self->lex_in_scope("&do") ? "CORE::do" : "do")
	     . " {\n\t". $self->deparse($op->first, $cx) ."\n\b};";
    } elsif (!null($op->first->sibling) and
	     $op->first->sibling->name eq "null" and
	     class($op->first->sibling) eq "UNOP" and
	     $op->first->sibling->first->flags & OPf_STACKED and
	     $op->first->sibling->first->name eq "rcatline") {
	return $self->maybe_parens($self->deparse($op->first, 18) . " .= "
				   . $self->deparse($op->first->sibling, 18),
				   $cx, 18);
    } else {
	return $self->deparse($op->first, $cx);
    }
}

sub padname {
    my $self = shift;
    my $targ = shift;
    return $self->padname_sv($targ)->PVX;
}

sub padany {
    my $self = shift;
    my $op = shift;
    return substr($self->padname($op->targ), 1); # skip $/@/%
}

sub pp_padsv {
    my $self = shift;
    my($op, $cx, $forbid_parens) = @_;
    my $targ = $op->targ;
    return $self->maybe_my($op, $cx, $self->padname($targ),
			   $self->padname_sv($targ),
			   $forbid_parens);
}

sub pp_padav { pp_padsv(@_) }
sub pp_padhv { pp_padsv(@_) }

sub gv_or_padgv {
    my $self = shift;
    my $op = shift;
    if (class($op) eq "PADOP") {
	return $self->padval($op->padix);
    } else { # class($op) eq "SVOP"
	return $op->gv;
    }
}

sub pp_gvsv {
    my $self = shift;
    my($op, $cx) = @_;
    my $gv = $self->gv_or_padgv($op);
    return $self->maybe_local($op, $cx, $self->stash_variable("\$",
				 $self->gv_name($gv), $cx));
}

sub pp_gv {
    my $self = shift;
    my($op, $cx) = @_;
    my $gv = $self->gv_or_padgv($op);
    return $self->gv_name($gv);
}

sub pp_aelemfast_lex {
    my $self = shift;
    my($op, $cx) = @_;
    my $name = $self->padname($op->targ);
    $name =~ s/^@/\$/;
    my $i = $op->private;
    $i -= 256 if $i > 127;
    return $name . "[" .  ($i + $self->{'arybase'}) . "]";
}

sub pp_aelemfast {
    my $self = shift;
    my($op, $cx) = @_;
    # optimised PADAV, pre 5.15
    return $self->pp_aelemfast_lex(@_) if ($op->flags & OPf_SPECIAL);

    my $gv = $self->gv_or_padgv($op);
    my($name,$quoted) = $self->stash_variable_name('@',$gv);
    $name = $quoted ? "$name->" : '$' . $name;
    my $i = $op->private;
    $i -= 256 if $i > 127;
    return $name . "[" .  ($i + $self->{'arybase'}) . "]";
}

sub rv2x {
    my $self = shift;
    my($op, $cx, $type) = @_;

    if (class($op) eq 'NULL' || !$op->can("first")) {
	carp("Unexpected op in pp_rv2x");
	return 'XXX';
    }
    my $kid = $op->first;
    if ($kid->name eq "gv") {
	return $self->stash_variable($type, $self->deparse($kid, 0), $cx);
    } elsif (is_scalar $kid) {
	my $str = $self->deparse($kid, 0);
	if ($str =~ /^\$([^\w\d])\z/) {
	    # "$$+" isn't a legal way to write the scalar dereference
	    # of $+, since the lexer can't tell you aren't trying to
	    # do something like "$$ + 1" to get one more than your
	    # PID. Either "${$+}" or "$${+}" are workable
	    # disambiguations, but if the programmer did the former,
	    # they'd be in the "else" clause below rather than here.
	    # It's not clear if this should somehow be unified with
	    # the code in dq and re_dq that also adds lexer
	    # disambiguation braces.
	    $str = '$' . "{$1}"; #'
	}
	return $type . $str;
    } else {
	return $type . "{" . $self->deparse($kid, 0) . "}";
    }
}

sub pp_rv2sv { maybe_local(@_, rv2x(@_, "\$")) }
sub pp_rv2hv { maybe_local(@_, rv2x(@_, "%")) }
sub pp_rv2gv { maybe_local(@_, rv2x(@_, "*")) }

# skip rv2av
sub pp_av2arylen {
    my $self = shift;
    my($op, $cx) = @_;
    if ($op->first->name eq "padav") {
	return $self->maybe_local($op, $cx, '$#' . $self->padany($op->first));
    } else {
	return $self->maybe_local($op, $cx,
				  $self->rv2x($op->first, $cx, '$#'));
    }
}

# skip down to the old, ex-rv2cv
sub pp_rv2cv {
    my ($self, $op, $cx) = @_;
    if (!null($op->first) && $op->first->name eq 'null' &&
	$op->first->targ == OP_LIST)
    {
	return $self->rv2x($op->first->first->sibling, $cx, "&")
    }
    else {
	return $self->rv2x($op, $cx, "")
    }
}

sub list_const {
    my $self = shift;
    my($cx, @list) = @_;
    my @a = map $self->const($_, 6), @list;
    if (@a == 0) {
	return "()";
    } elsif (@a == 1) {
	return $a[0];
    } elsif ( @a > 2 and !grep(!/^-?\d+$/, @a)) {
	# collapse (-1,0,1,2) into (-1..2)
	my ($s, $e) = @a[0,-1];
	my $i = $s;
	return $self->maybe_parens("$s..$e", $cx, 9)
	  unless grep $i++ != $_, @a;
    }
    return $self->maybe_parens(join(", ", @a), $cx, 6);
}

sub pp_rv2av {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first;
    if ($kid->name eq "const") { # constant list
	my $av = $self->const_sv($kid);
	return $self->list_const($cx, $av->ARRAY);
    } else {
	return $self->maybe_local($op, $cx, $self->rv2x($op, $cx, "\@"));
    }
 }

sub is_subscriptable {
    my $op = shift;
    if ($op->name =~ /^([ahg]elem|multideref$)/) {
	return 1;
    } elsif ($op->name eq "entersub") {
	my $kid = $op->first;
	return 0 unless null $kid->sibling;
	$kid = $kid->first;
	$kid = $kid->sibling until null $kid->sibling;
	return 0 if is_scope($kid);
	$kid = $kid->first;
	return 0 if $kid->name eq "gv" || $kid->name eq "padcv";
	return 0 if is_scalar($kid);
	return is_subscriptable($kid);	
    } else {
	return 0;
    }
}

sub elem_or_slice_array_name
{
    my $self = shift;
    my ($array, $left, $padname, $allow_arrow) = @_;

    if ($array->name eq $padname) {
	return $self->padany($array);
    } elsif (is_scope($array)) { # ${expr}[0]
	return "{" . $self->deparse($array, 0) . "}";
    } elsif ($array->name eq "gv") {
	($array, my $quoted) =
	    $self->stash_variable_name(
		$left eq '[' ? '@' : '%', $self->gv_or_padgv($array)
	    );
	if (!$allow_arrow && $quoted) {
	    # This cannot happen.
	    die "Invalid variable name $array for slice";
	}
	return $quoted ? "$array->" : $array;
    } elsif (!$allow_arrow || is_scalar $array) { # $x[0], $$x[0], ...
	return $self->deparse($array, 24);
    } else {
	return undef;
    }
}

sub elem_or_slice_single_index
{
    my $self = shift;
    my ($idx) = @_;

    $idx = $self->deparse($idx, 1);

    # Outer parens in an array index will confuse perl
    # if we're interpolating in a regular expression, i.e.
    # /$x$foo[(-1)]/ is *not* the same as /$x$foo[-1]/
    #
    # If $self->{parens}, then an initial '(' will
    # definitely be paired with a final ')'. If
    # !$self->{parens}, the misleading parens won't
    # have been added in the first place.
    #
    # [You might think that we could get "(...)...(...)"
    # where the initial and final parens do not match
    # each other. But we can't, because the above would
    # only happen if there's an infix binop between the
    # two pairs of parens, and *that* means that the whole
    # expression would be parenthesized as well.]
    #
    $idx =~ s/^\((.*)\)$/$1/ if $self->{'parens'};

    # Hash-element braces will autoquote a bareword inside themselves.
    # We need to make sure that C<$hash{warn()}> doesn't come out as
    # C<$hash{warn}>, which has a quite different meaning. Currently
    # B::Deparse will always quote strings, even if the string was a
    # bareword in the original (i.e. the OPpCONST_BARE flag is ignored
    # for constant strings.) So we can cheat slightly here - if we see
    # a bareword, we know that it is supposed to be a function call.
    #
    $idx =~ s/^([A-Za-z_]\w*)$/$1()/;

    return $idx;
}

sub elem {
    my $self = shift;
    my ($op, $cx, $left, $right, $padname) = @_;
    my($array, $idx) = ($op->first, $op->first->sibling);

    $idx = $self->elem_or_slice_single_index($idx);

    unless ($array->name eq $padname) { # Maybe this has been fixed	
	$array = $array->first; # skip rv2av (or ex-rv2av in _53+)
    }
    if (my $array_name=$self->elem_or_slice_array_name
	    ($array, $left, $padname, 1)) {
	return ($array_name =~ /->\z/
		    ? $array_name
		    : $array_name eq '#' ? '${#}' : "\$" . $array_name)
	      . $left . $idx . $right;
    } else {
	# $x[20][3]{hi} or expr->[20]
	my $arrow = is_subscriptable($array) ? "" : "->";
	return $self->deparse($array, 24) . $arrow . $left . $idx . $right;
    }

}

# a simplified version of elem_or_slice_array_name()
# for the use of pp_multideref

sub multideref_var_name {
    my $self = shift;
    my ($gv, $is_hash) = @_;

    my ($name, $quoted) =
        $self->stash_variable_name( $is_hash  ? '%' : '@', $gv);
    return $quoted ? "$name->"
                   : $name eq '#'
                        ? '${#}'       # avoid ${#}[1] => $#[1]
                        : '$' . $name;
}


sub pp_multideref {
    my $self = shift;
    my($op, $cx) = @_;
    my $text = "";

    if ($op->private & OPpMULTIDEREF_EXISTS) {
        $text = $self->keyword("exists"). " ";
    }
    elsif ($op->private & OPpMULTIDEREF_DELETE) {
        $text = $self->keyword("delete"). " ";
    }
    elsif ($op->private & OPpLVAL_INTRO) {
        $text = $self->keyword("local"). " ";
    }

    if ($op->first && ($op->first->flags & OPf_KIDS)) {
        # arbitrary initial expression, e.g. f(1,2,3)->[...]
        $text .=  $self->deparse($op->first, 24);
    }

    my @items = $op->aux_list($self->{curcv});
    my $actions = shift @items;

    my $is_hash;
    my $derefs = 0;

    while (1) {
        if (($actions & MDEREF_ACTION_MASK) == MDEREF_reload) {
            $actions = shift @items;
            next;
        }

        $is_hash = (
           ($actions & MDEREF_ACTION_MASK) == MDEREF_HV_pop_rv2hv_helem
        || ($actions & MDEREF_ACTION_MASK) == MDEREF_HV_gvsv_vivify_rv2hv_helem
        || ($actions & MDEREF_ACTION_MASK) == MDEREF_HV_padsv_vivify_rv2hv_helem
        || ($actions & MDEREF_ACTION_MASK) == MDEREF_HV_vivify_rv2hv_helem
        || ($actions & MDEREF_ACTION_MASK) == MDEREF_HV_padhv_helem
        || ($actions & MDEREF_ACTION_MASK) == MDEREF_HV_gvhv_helem
        );

        if (   ($actions & MDEREF_ACTION_MASK) == MDEREF_AV_padav_aelem
            || ($actions & MDEREF_ACTION_MASK) == MDEREF_HV_padhv_helem)
        {
            $derefs = 1;
            $text .= '$' . substr($self->padname(shift @items), 1);
        }
        elsif (   ($actions & MDEREF_ACTION_MASK) == MDEREF_AV_gvav_aelem
               || ($actions & MDEREF_ACTION_MASK) == MDEREF_HV_gvhv_helem)
        {
            $derefs = 1;
            $text .= $self->multideref_var_name(shift @items, $is_hash);
        }
        else {
            if (   ($actions & MDEREF_ACTION_MASK) ==
                                        MDEREF_AV_padsv_vivify_rv2av_aelem
                || ($actions & MDEREF_ACTION_MASK) ==
                                        MDEREF_HV_padsv_vivify_rv2hv_helem)
            {
                $text .= $self->padname(shift @items);
            }
            elsif (   ($actions & MDEREF_ACTION_MASK) ==
                                           MDEREF_AV_gvsv_vivify_rv2av_aelem
                   || ($actions & MDEREF_ACTION_MASK) ==
                                           MDEREF_HV_gvsv_vivify_rv2hv_helem)
            {
                $text .= $self->multideref_var_name(shift @items, $is_hash);
            }
            elsif (   ($actions & MDEREF_ACTION_MASK) ==
                                           MDEREF_AV_pop_rv2av_aelem
                   || ($actions & MDEREF_ACTION_MASK) ==
                                           MDEREF_HV_pop_rv2hv_helem)
            {
                if (   ($op->flags & OPf_KIDS)
                    && (   _op_is_or_was($op->first, OP_RV2AV)
                        || _op_is_or_was($op->first, OP_RV2HV))
                    && ($op->first->flags & OPf_KIDS)
                    && (   _op_is_or_was($op->first->first, OP_AELEM)
                        || _op_is_or_was($op->first->first, OP_HELEM))
                    )
                {
                    $derefs++;
                }
            }

            $text .= '->' if !$derefs++;
        }


        if (($actions & MDEREF_INDEX_MASK) == MDEREF_INDEX_none) {
            last;
        }

        $text .= $is_hash ? '{' : '[';

        if (($actions & MDEREF_INDEX_MASK) == MDEREF_INDEX_const) {
            my $key = shift @items;
            if ($is_hash) {
                $text .= $self->const($key, $cx);
            }
            else {
                $text .= $key;
            }
        }
        elsif (($actions & MDEREF_INDEX_MASK) == MDEREF_INDEX_padsv) {
            $text .= $self->padname(shift @items);
        }
        elsif (($actions & MDEREF_INDEX_MASK) == MDEREF_INDEX_gvsv) {
            $text .= '$' .  ($self->stash_variable_name('$', shift @items))[0];
        }

        $text .= $is_hash ? '}' : ']';

        if ($actions & MDEREF_FLAG_last) {
            last;
        }
        $actions >>= MDEREF_SHIFT;
    }

    return $text;
}


sub pp_aelem { maybe_local(@_, elem(@_, "[", "]", "padav")) }
sub pp_helem { maybe_local(@_, elem(@_, "{", "}", "padhv")) }

sub pp_gelem {
    my $self = shift;
    my($op, $cx) = @_;
    my($glob, $part) = ($op->first, $op->last);
    $glob = $glob->first; # skip rv2gv
    $glob = $glob->first if $glob->name eq "rv2gv"; # this one's a bug
    my $scope = is_scope($glob);
    $glob = $self->deparse($glob, 0);
    $part = $self->deparse($part, 1);
    return "*" . ($scope ? "{$glob}" : $glob) . "{$part}";
}

sub slice {
    my $self = shift;
    my ($op, $cx, $left, $right, $regname, $padname) = @_;
    my $last;
    my(@elems, $kid, $array, $list);
    if (class($op) eq "LISTOP") {
	$last = $op->last;
    } else { # ex-hslice inside delete()
	for ($kid = $op->first; !null $kid->sibling; $kid = $kid->sibling) {}
	$last = $kid;
    }
    $array = $last;
    $array = $array->first
	if $array->name eq $regname or $array->name eq "null";
    $array = $self->elem_or_slice_array_name($array,$left,$padname,0);
    $kid = $op->first->sibling; # skip pushmark
    if ($kid->name eq "list") {
	$kid = $kid->first->sibling; # skip list, pushmark
	for (; !null $kid; $kid = $kid->sibling) {
	    push @elems, $self->deparse($kid, 6);
	}
	$list = join(", ", @elems);
    } else {
	$list = $self->elem_or_slice_single_index($kid);
    }
    my $lead = '@';
    $lead = '%' if $op->name =~ /^kv/i;
    return $lead . $array . $left . $list . $right;
}

sub pp_aslice   { maybe_local(@_, slice(@_, "[", "]", "rv2av", "padav")) }
sub pp_kvaslice {                 slice(@_, "[", "]", "rv2av", "padav")  }
sub pp_hslice   { maybe_local(@_, slice(@_, "{", "}", "rv2hv", "padhv")) }
sub pp_kvhslice {                 slice(@_, "{", "}", "rv2hv", "padhv")  }

sub pp_lslice {
    my $self = shift;
    my($op, $cx) = @_;
    my $idx = $op->first;
    my $list = $op->last;
    my(@elems, $kid);
    $list = $self->deparse($list, 1);
    $idx = $self->deparse($idx, 1);
    return "($list)" . "[$idx]";
}

sub want_scalar {
    my $op = shift;
    return ($op->flags & OPf_WANT) == OPf_WANT_SCALAR;
}

sub want_list {
    my $op = shift;
    return ($op->flags & OPf_WANT) == OPf_WANT_LIST;
}

sub _method {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first->sibling; # skip pushmark
    my($meth, $obj, @exprs);
    if ($kid->name eq "list" and want_list $kid) {
	# When an indirect object isn't a bareword but the args are in
	# parens, the parens aren't part of the method syntax (the LLAFR
	# doesn't apply), but they make a list with OPf_PARENS set that
	# doesn't get flattened by the append_elem that adds the method,
	# making a (object, arg1, arg2, ...) list where the object
	# usually is. This can be distinguished from
	# '($obj, $arg1, $arg2)->meth()' (which is legal if $arg2 is an
	# object) because in the later the list is in scalar context
	# as the left side of -> always is, while in the former
	# the list is in list context as method arguments always are.
	# (Good thing there aren't method prototypes!)
	$meth = $kid->sibling;
	$kid = $kid->first->sibling; # skip pushmark
	$obj = $kid;
	$kid = $kid->sibling;
	for (; not null $kid; $kid = $kid->sibling) {
	    push @exprs, $kid;
	}
    } else {
	$obj = $kid;
	$kid = $kid->sibling;
	for (; !null ($kid->sibling) && $kid->name!~/^method(?:_named)?\z/;
	      $kid = $kid->sibling) {
	    push @exprs, $kid
	}
	$meth = $kid;
    }

    if ($meth->name eq "method_named") {
	$meth = $self->meth_sv($meth)->PV;
    } elsif ($meth->name eq "method_super") {
	$meth = "SUPER::".$self->meth_sv($meth)->PV;
    } elsif ($meth->name eq "method_redir") {
        $meth = $self->meth_rclass_sv($meth)->PV.'::'.$self->meth_sv($meth)->PV;
    } elsif ($meth->name eq "method_redir_super") {
        $meth = $self->meth_rclass_sv($meth)->PV.'::SUPER::'.
                $self->meth_sv($meth)->PV;
    } else {
	$meth = $meth->first;
	if ($meth->name eq "const") {
	    # As of 5.005_58, this case is probably obsoleted by the
	    # method_named case above
	    $meth = $self->const_sv($meth)->PV; # needs to be bare
	}
    }

    return { method => $meth, variable_method => ref($meth),
             object => $obj, args => \@exprs  },
	   $cx;
}

# compat function only
sub method {
    my $self = shift;
    my $info = $self->_method(@_);
    return $self->e_method( $self->_method(@_) );
}

sub e_method {
    my ($self, $info, $cx) = @_;
    my $obj = $self->deparse($info->{object}, 24);

    my $meth = $info->{method};
    $meth = $self->deparse($meth, 1) if $info->{variable_method};
    my $args = join(", ", map { $self->deparse($_, 6) } @{$info->{args}} );
    if ($info->{object}->name eq 'scope' && want_list $info->{object}) {
	# method { $object }
	# This must be deparsed this way to preserve list context
	# of $object.
	my $need_paren = $cx >= 6;
	return '(' x $need_paren
	     . $meth . substr($obj,2) # chop off the "do"
	     . " $args"
	     . ')' x $need_paren;
    }
    my $kid = $obj . "->" . $meth;
    if (length $args) {
	return $kid . "(" . $args . ")"; # parens mandatory
    } else {
	return $kid;
    }
}

# returns "&" if the prototype doesn't match the args,
# or ("", $args_after_prototype_demunging) if it does.
sub check_proto {
    my $self = shift;
    return "&" if $self->{'noproto'};
    my($proto, @args) = @_;
    my($arg, $real);
    my $doneok = 0;
    my @reals;
    # An unbackslashed @ or % gobbles up the rest of the args
    1 while $proto =~ s/(?<!\\)([@%])[^\]]+$/$1/;
    $proto =~ s/^\s*//;
    while ($proto) {
	$proto =~ s/^(\\?[\$\@&%*_]|\\\[[\$\@&%*]+\]|;|)\s*//;
	my $chr = $1;
	if ($chr eq "") {
	    return "&" if @args;
	} elsif ($chr eq ";") {
	    $doneok = 1;
	} elsif ($chr eq "@" or $chr eq "%") {
	    push @reals, map($self->deparse($_, 6), @args);
	    @args = ();
	} else {
	    $arg = shift @args;
	    last unless $arg;
	    if ($chr eq "\$" || $chr eq "_") {
		if (want_scalar $arg) {
		    push @reals, $self->deparse($arg, 6);
		} else {
		    return "&";
		}
	    } elsif ($chr eq "&") {
		if ($arg->name =~ /^(s?refgen|undef)$/) {
		    push @reals, $self->deparse($arg, 6);
		} else {
		    return "&";
		}
	    } elsif ($chr eq "*") {
		if ($arg->name =~ /^s?refgen$/
		    and $arg->first->first->name eq "rv2gv")
		  {
		      $real = $arg->first->first; # skip refgen, null
		      if ($real->first->name eq "gv") {
			  push @reals, $self->deparse($real, 6);
		      } else {
			  push @reals, $self->deparse($real->first, 6);
		      }
		  } else {
		      return "&";
		  }
	    } elsif (substr($chr, 0, 1) eq "\\") {
		$chr =~ tr/\\[]//d;
		if ($arg->name =~ /^s?refgen$/ and
		    !null($real = $arg->first) and
		    ($chr =~ /\$/ && is_scalar($real->first)
		     or ($chr =~ /@/
			 && class($real->first->sibling) ne 'NULL'
			 && $real->first->sibling->name
			 =~ /^(rv2|pad)av$/)
		     or ($chr =~ /%/
			 && class($real->first->sibling) ne 'NULL'
			 && $real->first->sibling->name
			 =~ /^(rv2|pad)hv$/)
		     #or ($chr =~ /&/ # This doesn't work
		     #   && $real->first->name eq "rv2cv")
		     or ($chr =~ /\*/
			 && $real->first->name eq "rv2gv")))
		  {
		      push @reals, $self->deparse($real, 6);
		  } else {
		      return "&";
		  }
	    }
       }
    }
    return "&" if $proto and !$doneok; # too few args and no ';'
    return "&" if @args;               # too many args
    return ("", join ", ", @reals);
}

sub retscalar {
    my $name = $_[0]->name;
    # XXX There has to be a better way of doing this scalar-op check.
    #     Currently PL_opargs is not exposed.
    if ($name eq 'null') {
        $name = substr B::ppname($_[0]->targ), 3
    }
    $name =~ /^(?:scalar|pushmark|wantarray|const|gvsv|gv|padsv|rv2gv
                 |rv2sv|av2arylen|anoncode|prototype|srefgen|ref|bless
                 |regcmaybe|regcreset|regcomp|qr|subst|substcont|trans
                 |transr|sassign|chop|schop|chomp|schomp|defined|undef
                 |study|pos|preinc|i_preinc|predec|i_predec|postinc
                 |i_postinc|postdec|i_postdec|pow|multiply|i_multiply
                 |divide|i_divide|modulo|i_modulo|add|i_add|subtract
                 |i_subtract|concat|stringify|left_shift|right_shift|lt
                 |i_lt|gt|i_gt|le|i_le|ge|i_ge|eq|i_eq|ne|i_ne|ncmp|i_ncmp
                 |slt|sgt|sle|sge|seq|sne|scmp|[sn]?bit_(?:and|x?or)|negate
                 |i_negate|not|[sn]?complement|smartmatch|atan2|sin|cos
                 |rand|srand|exp|log|sqrt|int|hex|oct|abs|length|substr
                 |vec|index|rindex|sprintf|formline|ord|chr|crypt|ucfirst
                 |lcfirst|uc|lc|quotemeta|aelemfast|aelem|exists|helem
                 |pack|join|anonlist|anonhash|push|pop|shift|unshift|xor
                 |andassign|orassign|dorassign|warn|die|reset|nextstate
                 |dbstate|unstack|last|next|redo|dump|goto|exit|open|close
                 |pipe_op|fileno|umask|binmode|tie|untie|tied|dbmopen
                 |dbmclose|select|getc|read|enterwrite|prtf|print|say
                 |sysopen|sysseek|sysread|syswrite|eof|tell|seek|truncate
                 |fcntl|ioctl|flock|send|recv|socket|sockpair|bind|connect
                 |listen|accept|shutdown|gsockopt|ssockopt|getsockname
                 |getpeername|ftrread|ftrwrite|ftrexec|fteread|ftewrite
                 |fteexec|ftis|ftsize|ftmtime|ftatime|ftctime|ftrowned
                 |fteowned|ftzero|ftsock|ftchr|ftblk|ftfile|ftdir|ftpipe
                 |ftsuid|ftsgid|ftsvtx|ftlink|fttty|fttext|ftbinary|chdir
                 |chown|chroot|unlink|chmod|utime|rename|link|symlink
                 |readlink|mkdir|rmdir|open_dir|telldir|seekdir|rewinddir
                 |closedir|fork|wait|waitpid|system|exec|kill|getppid
                 |getpgrp|setpgrp|getpriority|setpriority|time|alarm|sleep
                 |shmget|shmctl|shmread|shmwrite|msgget|msgctl|msgsnd
                 |msgrcv|semop|semget|semctl|hintseval|shostent|snetent
                 |sprotoent|sservent|ehostent|enetent|eprotoent|eservent
                 |spwent|epwent|sgrent|egrent|getlogin|syscall|lock|runcv
                 |fc)\z/x
}

sub pp_entersub {
    my $self = shift;
    my($op, $cx) = @_;
    return $self->e_method($self->_method($op, $cx))
        unless null $op->first->sibling;
    my $prefix = "";
    my $amper = "";
    my($kid, @exprs);
    if ($op->flags & OPf_SPECIAL && !($op->flags & OPf_MOD)) {
	$prefix = "do ";
    } elsif ($op->private & OPpENTERSUB_AMPER) {
	$amper = "&";
    }
    $kid = $op->first;
    $kid = $kid->first->sibling; # skip ex-list, pushmark
    for (; not null $kid->sibling; $kid = $kid->sibling) {
	push @exprs, $kid;
    }
    my $simple = 0;
    my $proto = undef;
    my $lexical;
    if (is_scope($kid)) {
	$amper = "&";
	$kid = "{" . $self->deparse($kid, 0) . "}";
    } elsif ($kid->first->name eq "gv") {
	my $gv = $self->gv_or_padgv($kid->first);
	my $cv;
	if (class($gv) eq 'GV' && class($cv = $gv->CV) ne "SPECIAL"
	 || $gv->FLAGS & SVf_ROK && class($cv = $gv->RV) eq 'CV') {
	    $proto = $cv->PV if $cv->FLAGS & SVf_POK;
	}
	$simple = 1; # only calls of named functions can be prototyped
	$kid = $self->deparse($kid, 24);
	my $fq;
	# Fully qualify any sub name that conflicts with a lexical.
	if ($self->lex_in_scope("&$kid")
	 || $self->lex_in_scope("&$kid", 1))
	{
	    $fq++;
	} elsif (!$amper) {
	    if ($kid eq 'main::') {
		$kid = '::';
	    }
	    else {
	      if ($kid !~ /::/ && $kid ne 'x') {
		# Fully qualify any sub name that is also a keyword.  While
		# we could check the import flag, we cannot guarantee that
		# the code deparsed so far would set that flag, so we qual-
		# ify the names regardless of importation.
		if (exists $feature_keywords{$kid}) {
		    $fq++ if $self->feature_enabled($kid);
		} elsif (do { local $@; local $SIG{__DIE__};
			      eval { () = prototype "CORE::$kid"; 1 } }) {
		    $fq++
		}
	      }
	      if ($kid !~ /^(?:\w|::)(?:[\w\d]|::(?!\z))*\z/) {
		$kid = single_delim("q", "'", $kid, $self) . '->';
	      }
	    }
	}
	$fq and substr $kid, 0, 0, = $self->{'curstash'}.'::';
    } elsif (is_scalar ($kid->first) && $kid->first->name ne 'rv2cv') {
	$amper = "&";
	$kid = $self->deparse($kid, 24);
    } else {
	$prefix = "";
	my $grandkid = $kid->first;
	my $arrow = ($lexical = $grandkid->name eq "padcv")
		 || is_subscriptable($grandkid)
		    ? ""
		    : "->";
	$kid = $self->deparse($kid, 24) . $arrow;
	if ($lexical) {
	    my $padlist = $self->{'curcv'}->PADLIST;
	    my $padoff = $grandkid->targ;
	    my $padname = $padlist->ARRAYelt(0)->ARRAYelt($padoff);
	    my $protocv = $padname->FLAGS & SVpad_STATE
		? $padlist->ARRAYelt(1)->ARRAYelt($padoff)
		: $padname->PROTOCV;
	    if ($protocv->FLAGS & SVf_POK) {
		$proto = $protocv->PV
	    }
	    $simple = 1;
	}
    }

    # Doesn't matter how many prototypes there are, if
    # they haven't happened yet!
    my $declared = $lexical || exists $self->{'subs_declared'}{$kid};
    if (not $declared and $self->{'in_coderef2text'}) {
	no strict 'refs';
	no warnings 'uninitialized';
	$declared =
	       (
		 defined &{ ${$self->{'curstash'}."::"}{$kid} }
		 && !exists
		     $self->{'subs_deparsed'}{$self->{'curstash'}."::".$kid}
		 && defined prototype $self->{'curstash'}."::".$kid
	       );
    }
    if (!$declared && defined($proto)) {
	# Avoid "too early to check prototype" warning
	($amper, $proto) = ('&');
    }

    my $args;
    my $listargs = 1;
    if ($declared and defined $proto and not $amper) {
	($amper, $args) = $self->check_proto($proto, @exprs);
	$listargs = $amper;
    }
    if ($listargs) {
	$args = join(", ", map(
		    ($_->flags & OPf_WANT) == OPf_WANT_SCALAR
		 && !retscalar($_)
			? $self->maybe_parens_unop('scalar', $_, 6)
			: $self->deparse($_, 6),
		    @exprs
		));
    }
    if ($prefix or $amper) {
	if ($kid eq '&') { $kid = "{$kid}" } # &{&} cannot be written as &&
	if ($op->flags & OPf_STACKED) {
	    return $prefix . $amper . $kid . "(" . $args . ")";
	} else {
	    return $prefix . $amper. $kid;
	}
    } else {
	# It's a syntax error to call CORE::GLOBAL::foo with a prefix,
	# so it must have been translated from a keyword call. Translate
	# it back.
	$kid =~ s/^CORE::GLOBAL:://;

	my $dproto = defined($proto) ? $proto : "undefined";
	my $scalar_proto = $dproto =~ /^;*(?:[\$*_+]|\\.|\\\[[^]]\])\z/;
        if (!$declared) {
	    return "$kid(" . $args . ")";
	} elsif ($dproto =~ /^\s*\z/) {
	    return $kid;
	} elsif ($scalar_proto and is_scalar($exprs[0])) {
	    # is_scalar is an excessively conservative test here:
	    # really, we should be comparing to the precedence of the
	    # top operator of $exprs[0] (ala unop()), but that would
	    # take some major code restructuring to do right.
	    return $self->maybe_parens_func($kid, $args, $cx, 16);
	} elsif (not $scalar_proto and defined($proto) || $simple) { #'
	    return $self->maybe_parens_func($kid, $args, $cx, 5);
	} else {
	    return "$kid(" . $args . ")";
	}
    }
}

sub pp_enterwrite { unop(@_, "write") }

# escape things that cause interpolation in double quotes,
# but not character escapes
sub uninterp {
    my($str) = @_;
    $str =~ s/(^|\G|[^\\])((?:\\\\)*)([\$\@]|\\[uUlLQE])/$1$2\\$3/g;
    return $str;
}

{
my $bal;
BEGIN {
    use re "eval";
    # Matches any string which is balanced with respect to {braces}
    $bal = qr(
      (?:
	[^\\{}]
      | \\\\
      | \\[{}]
      | \{(??{$bal})\}
      )*
    )x;
}

# the same, but treat $|, $), $( and $ at the end of the string differently
# and leave comments unmangled for the sake of /x and (?x).
sub re_uninterp {
    my($str) = @_;

    $str =~ s/
	  ( ^|\G                  # $1
          | [^\\]
          )

          (                       # $2
            (?:\\\\)*
          )

          (                       # $3
            ( \(\?\??\{$bal\}\)   # $4  (skip over (?{}) and (??{}) blocks)
            | \#[^\n]*            #     (skip over comments)
            )
          | [\$\@]
            (?!\||\)|\(|$|\s)
          | \\[uUlLQE]
          )

	/defined($4) && length($4) ? "$1$2$4" : "$1$2\\$3"/xeg;

    return $str;
}
}

# character escapes, but not delimiters that might need to be escaped
sub escape_str { # ASCII, UTF8
    my($str) = @_;
    $str =~ s/(.)/ord($1) > 255 ? sprintf("\\x{%x}", ord($1)) : $1/eg;
    $str =~ s/\a/\\a/g;
#    $str =~ s/\cH/\\b/g; # \b means something different in a regex; and \cH
                          # isn't a backspace in EBCDIC
    $str =~ s/\t/\\t/g;
    $str =~ s/\n/\\n/g;
    $str =~ s/\e/\\e/g;
    $str =~ s/\f/\\f/g;
    $str =~ s/\r/\\r/g;
    $str =~ s/([\cA-\cZ])/'\\c' . $unctrl{$1}/ge;
    $str =~ s/([[:^print:]])/sprintf("\\%03o", ord($1))/age;
    return $str;
}

# For regexes.  Leave whitespace unmangled in case of /x or (?x).
sub escape_re {
    my($str) = @_;
    $str =~ s/(.)/ord($1) > 255 ? sprintf("\\x{%x}", ord($1)) : $1/eg;
    $str =~ s/([[:^print:]])/
	($1 =~ y! \t\n!!) ? $1 : sprintf("\\%03o", ord($1))/age;
    $str =~ s/\n/\n\f/g;
    return $str;
}

# Don't do this for regexen
sub unback {
    my($str) = @_;
    $str =~ s/\\/\\\\/g;
    return $str;
}

# Remove backslashes which precede literal control characters,
# to avoid creating ambiguity when we escape the latter.
sub re_unback {
    my($str) = @_;

    # the insane complexity here is due to the behaviour of "\c\"
    $str =~ s/(^|[^\\]|\\c\\)(?<!\\c)\\(\\\\)*(?=[[:^print:]])/$1$2/g;
    return $str;
}

sub balanced_delim {
    my($str) = @_;
    my @str = split //, $str;
    my($ar, $open, $close, $fail, $c, $cnt, $last_bs);
    for $ar (['[',']'], ['(',')'], ['<','>'], ['{','}']) {
	($open, $close) = @$ar;
	$fail = 0; $cnt = 0; $last_bs = 0;
	for $c (@str) {
	    if ($c eq $open) {
		$fail = 1 if $last_bs;
		$cnt++;
	    } elsif ($c eq $close) {
		$fail = 1 if $last_bs;
		$cnt--;
		if ($cnt < 0) {
		    # qq()() isn't ")("
		    $fail = 1;
		    last;
		}
	    }
	    $last_bs = $c eq '\\';
	}
	$fail = 1 if $cnt != 0;
	return ($open, "$open$str$close") if not $fail;
    }
    return ("", $str);
}

sub single_delim {
    my($q, $default, $str, $self) = @_;
    return "$default$str$default" if $default and index($str, $default) == -1;
    my $coreq = $self->keyword($q); # maybe CORE::q
    if ($q ne 'qr') {
	(my $succeed, $str) = balanced_delim($str);
	return "$coreq$str" if $succeed;
    }
    for my $delim ('/', '"', '#') {
	return "$coreq$delim" . $str . $delim if index($str, $delim) == -1;
    }
    if ($default) {
	$str =~ s/$default/\\$default/g;
	return "$default$str$default";
    } else {
	$str =~ s[/][\\/]g;
	return "$coreq/$str/";
    }
}

my $max_prec;
BEGIN { $max_prec = int(0.999 + 8*length(pack("F", 42))*log(2)/log(10)); }

# Split a floating point number into an integer mantissa and a binary
# exponent. Assumes you've already made sure the number isn't zero or
# some weird infinity or NaN.
sub split_float {
    my($f) = @_;
    my $exponent = 0;
    if ($f == int($f)) {
	while ($f % 2 == 0) {
	    $f /= 2;
	    $exponent++;
	}
    } else {
	while ($f != int($f)) {
	    $f *= 2;
	    $exponent--;
	}
    }
    my $mantissa = sprintf("%.0f", $f);
    return ($mantissa, $exponent);
}

sub const {
    my $self = shift;
    my($sv, $cx) = @_;
    if ($self->{'use_dumper'}) {
	return $self->const_dumper($sv, $cx);
    }
    if (class($sv) eq "SPECIAL") {
	# sv_undef, sv_yes, sv_no
	return $$sv == 3 ? $self->maybe_parens("!1", $cx, 21)
			 : ('undef', '1')[$$sv-1];
    }
    if (class($sv) eq "NULL") {
       return 'undef';
    }
    # convert a version object into the "v1.2.3" string in its V magic
    if ($sv->FLAGS & SVs_RMG) {
	for (my $mg = $sv->MAGIC; $mg; $mg = $mg->MOREMAGIC) {
	    return $mg->PTR if $mg->TYPE eq 'V';
	}
    }

    if ($sv->FLAGS & SVf_IOK) {
	my $str = $sv->int_value;
	$str = $self->maybe_parens($str, $cx, 21) if $str < 0;
	return $str;
    } elsif ($sv->FLAGS & SVf_NOK) {
	my $nv = $sv->NV;
	if ($nv == 0) {
	    if (pack("F", $nv) eq pack("F", 0)) {
		# positive zero
		return "0";
	    } else {
		# negative zero
		return $self->maybe_parens("-.0", $cx, 21);
	    }
	} elsif (1/$nv == 0) {
	    if ($nv > 0) {
		# positive infinity
		return $self->maybe_parens("9**9**9", $cx, 22);
	    } else {
		# negative infinity
		return $self->maybe_parens("-9**9**9", $cx, 21);
	    }
	} elsif ($nv != $nv) {
	    # NaN
	    if (pack("F", $nv) eq pack("F", sin(9**9**9))) {
		# the normal kind
		return "sin(9**9**9)";
	    } elsif (pack("F", $nv) eq pack("F", -sin(9**9**9))) {
		# the inverted kind
		return $self->maybe_parens("-sin(9**9**9)", $cx, 21);
	    } else {
		# some other kind
		my $hex = unpack("h*", pack("F", $nv));
		return qq'unpack("F", pack("h*", "$hex"))';
	    }
	}
	# first, try the default stringification
	my $str = "$nv";
	if ($str != $nv) {
	    # failing that, try using more precision
	    $str = sprintf("%.${max_prec}g", $nv);
#	    if (pack("F", $str) ne pack("F", $nv)) {
	    if ($str != $nv) {
		# not representable in decimal with whatever sprintf()
		# and atof() Perl is using here.
		my($mant, $exp) = split_float($nv);
		return $self->maybe_parens("$mant * 2**$exp", $cx, 19);
	    }
	}
	$str = $self->maybe_parens($str, $cx, 21) if $nv < 0;
	return $str;
    } elsif ($sv->FLAGS & SVf_ROK && $sv->can("RV")) {
	my $ref = $sv->RV;
	my $class = class($ref);
	if ($class eq "AV") {
	    return "[" . $self->list_const(2, $ref->ARRAY) . "]";
	} elsif ($class eq "HV") {
	    my %hash = $ref->ARRAY;
	    my @elts;
	    for my $k (sort keys %hash) {
		push @elts, "$k => " . $self->const($hash{$k}, 6);
	    }
	    return "{" . join(", ", @elts) . "}";
	} elsif ($class eq "CV") {
	    BEGIN {
		if ($] > 5.0150051) {
		    require overloading;
		    unimport overloading;
		}
	    }
	    if ($] > 5.0150051 && $self->{curcv} &&
		 $self->{curcv}->object_2svref == $ref->object_2svref) {
		return $self->keyword("__SUB__");
	    }
	    return "sub " . $self->deparse_sub($ref);
	}
	if ($class ne 'SPECIAL' and $ref->FLAGS & SVs_SMG) {
	    for (my $mg = $ref->MAGIC; $mg; $mg = $mg->MOREMAGIC) {
		if ($mg->TYPE eq 'r') {
		    my $re = re_uninterp(escape_re(re_unback($mg->precomp)));
		    return single_delim("qr", "", $re, $self);
		}
	    }
	}
	
	my $const = $self->const($ref, 20);
	if ($self->{in_subst_repl} && $const =~ /^[0-9]/) {
	    $const = "($const)";
	}
	return $self->maybe_parens("\\$const", $cx, 20);
    } elsif ($sv->FLAGS & SVf_POK) {
	my $str = $sv->PV;
	if ($str =~ /[[:^print:]]/a) {
	    return single_delim("qq", '"',
				 uninterp(escape_str unback $str), $self);
	} else {
	    return single_delim("q", "'", unback($str), $self);
	}
    } else {
	return "undef";
    }
}

sub const_dumper {
    my $self = shift;
    my($sv, $cx) = @_;
    my $ref = $sv->object_2svref();
    my $dumper = Data::Dumper->new([$$ref], ['$v']);
    $dumper->Purity(1)->Terse(1)->Deparse(1)->Indent(0)->Useqq(1)->Sortkeys(1);
    my $str = $dumper->Dump();
    if ($str =~ /^\$v/) {
	return '${my ' . $str . ' \$v}';
    } else {
	return $str;
    }
}

sub const_sv {
    my $self = shift;
    my $op = shift;
    my $sv = $op->sv;
    # the constant could be in the pad (under useithreads)
    $sv = $self->padval($op->targ) unless $$sv;
    return $sv;
}

sub meth_sv {
    my $self = shift;
    my $op = shift;
    my $sv = $op->meth_sv;
    # the constant could be in the pad (under useithreads)
    $sv = $self->padval($op->targ) unless $$sv;
    return $sv;
}

sub meth_rclass_sv {
    my $self = shift;
    my $op = shift;
    my $sv = $op->rclass;
    # the constant could be in the pad (under useithreads)
    $sv = $self->padval($sv) unless ref $sv;
    return $sv;
}

sub pp_const {
    my $self = shift;
    my($op, $cx) = @_;
    if ($op->private & OPpCONST_ARYBASE) {
        return '$[';
    }
#    if ($op->private & OPpCONST_BARE) { # trouble with '=>' autoquoting
#	return $self->const_sv($op)->PV;
#    }
    my $sv = $self->const_sv($op);
    return $self->const($sv, $cx);
}

sub dq {
    my $self = shift;
    my $op = shift;
    my $type = $op->name;
    if ($type eq "const") {
	return '$[' if $op->private & OPpCONST_ARYBASE;
	return uninterp(escape_str(unback($self->const_sv($op)->as_string)));
    } elsif ($type eq "concat") {
	my $first = $self->dq($op->first);
	my $last  = $self->dq($op->last);

	# Disambiguate "${foo}bar", "${foo}{bar}", "${foo}[1]", "$foo\::bar"
	($last =~ /^[A-Z\\\^\[\]_?]/ &&
	    $first =~ s/([\$@])\^$/${1}{^}/)  # "${^}W" etc
	    || ($last =~ /^[:'{\[\w_]/ && #'
		$first =~ s/([\$@])([A-Za-z_]\w*)$/${1}{$2}/);

	return $first . $last;
    } elsif ($type eq "uc") {
	return '\U' . $self->dq($op->first->sibling) . '\E';
    } elsif ($type eq "lc") {
	return '\L' . $self->dq($op->first->sibling) . '\E';
    } elsif ($type eq "ucfirst") {
	return '\u' . $self->dq($op->first->sibling);
    } elsif ($type eq "lcfirst") {
	return '\l' . $self->dq($op->first->sibling);
    } elsif ($type eq "quotemeta") {
	return '\Q' . $self->dq($op->first->sibling) . '\E';
    } elsif ($type eq "fc") {
	return '\F' . $self->dq($op->first->sibling) . '\E';
    } elsif ($type eq "join") {
	return $self->deparse($op->last, 26); # was join($", @ary)
    } else {
	return $self->deparse($op, 26);
    }
}

sub pp_backtick {
    my $self = shift;
    my($op, $cx) = @_;
    # skip pushmark if it exists (readpipe() vs ``)
    my $child = $op->first->sibling->isa('B::NULL')
	? $op->first : $op->first->sibling;
    if ($self->pure_string($child)) {
	return single_delim("qx", '`', $self->dq($child, 1), $self);
    }
    unop($self, @_, "readpipe");
}

sub dquote {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first->sibling; # skip ex-stringify, pushmark
    return $self->deparse($kid, $cx) if $self->{'unquote'};
    $self->maybe_targmy($kid, $cx,
			sub {single_delim("qq", '"', $self->dq($_[1]),
					   $self)});
}

# OP_STRINGIFY is a listop, but it only ever has one arg
sub pp_stringify {
    my ($self, $op, $cx) = @_;
    my $kid = $op->first->sibling;
    while ($kid->name eq 'null' && !null($kid->first)) {
	$kid = $kid->first;
    }
    if ($kid->name =~ /^(?:const|padsv|rv2sv|av2arylen|gvsv|multideref
			  |aelemfast(?:_lex)?|[ah]elem|join|concat)\z/x) {
	maybe_targmy(@_, \&dquote);
    }
    else {
	# Actually an optimised join.
	my $result = listop(@_,"join");
	$result =~ s/join([( ])/join$1$self->{'ex_const'}, /;
	$result;
    }
}

# tr/// and s/// (and tr[][], tr[]//, tr###, etc)
# note that tr(from)/to/ is OK, but not tr/from/(to)
sub double_delim {
    my($from, $to) = @_;
    my($succeed, $delim);
    if ($from !~ m[/] and $to !~ m[/]) {
	return "/$from/$to/";
    } elsif (($succeed, $from) = balanced_delim($from) and $succeed) {
	if (($succeed, $to) = balanced_delim($to) and $succeed) {
	    return "$from$to";
	} else {
	    for $delim ('/', '"', '#') { # note no "'" -- s''' is special
		return "$from$delim$to$delim" if index($to, $delim) == -1;
	    }
	    $to =~ s[/][\\/]g;
	    return "$from/$to/";
	}
    } else {
	for $delim ('/', '"', '#') { # note no '
	    return "$delim$from$delim$to$delim"
		if index($to . $from, $delim) == -1;
	}
	$from =~ s[/][\\/]g;
	$to =~ s[/][\\/]g;
	return "/$from/$to/";	
    }
}

# Only used by tr///, so backslashes hyphens
sub pchr { # ASCII
    my($n) = @_;
    if ($n == ord '\\') {
	return '\\\\';
    } elsif ($n == ord "-") {
	return "\\-";
    } elsif (utf8::native_to_unicode($n) >= utf8::native_to_unicode(ord(' '))
             and utf8::native_to_unicode($n) <= utf8::native_to_unicode(ord('~')))
    {
        # I'm presuming a regex is not ok here, otherwise we could have used
        # /[[:print:]]/a to get here
	return chr($n);
    } elsif ($n == ord "\a") {
	return '\\a';
    } elsif ($n == ord "\b") {
	return '\\b';
    } elsif ($n == ord "\t") {
	return '\\t';
    } elsif ($n == ord "\n") {
	return '\\n';
    } elsif ($n == ord "\e") {
	return '\\e';
    } elsif ($n == ord "\f") {
	return '\\f';
    } elsif ($n == ord "\r") {
	return '\\r';
    } elsif ($n >= ord("\cA") and $n <= ord("\cZ")) {
	return '\\c' . unctrl{chr $n};
    } else {
#	return '\x' . sprintf("%02x", $n);
	return '\\' . sprintf("%03o", $n);
    }
}

sub collapse {
    my(@chars) = @_;
    my($str, $c, $tr) = ("");
    for ($c = 0; $c < @chars; $c++) {
	$tr = $chars[$c];
	$str .= pchr($tr);
	if ($c <= $#chars - 2 and $chars[$c + 1] == $tr + 1 and
	    $chars[$c + 2] == $tr + 2)
	{
	    for (; $c <= $#chars-1 and $chars[$c + 1] == $chars[$c] + 1; $c++)
	      {}
	    $str .= "-";
	    $str .= pchr($chars[$c]);
	}
    }
    return $str;
}

sub tr_decode_byte {
    my($table, $flags) = @_;
    my(@table) = unpack("s*", $table);
    splice @table, 0x100, 1;   # Number of subsequent elements
    my($c, $tr, @from, @to, @delfrom, $delhyphen);
    if ($table[ord "-"] != -1 and
	$table[ord("-") - 1] == -1 || $table[ord("-") + 1] == -1)
    {
	$tr = $table[ord "-"];
	$table[ord "-"] = -1;
	if ($tr >= 0) {
	    @from = ord("-");
	    @to = $tr;
	} else { # -2 ==> delete
	    $delhyphen = 1;
	}
    }
    for ($c = 0; $c < @table; $c++) {
	$tr = $table[$c];
	if ($tr >= 0) {
	    push @from, $c; push @to, $tr;
	} elsif ($tr == -2) {
	    push @delfrom, $c;
	}
    }
    @from = (@from, @delfrom);
    if ($flags & OPpTRANS_COMPLEMENT) {
	my @newfrom = ();
	my %from;
	@from{@from} = (1) x @from;
	for ($c = 0; $c < 256; $c++) {
	    push @newfrom, $c unless $from{$c};
	}
	@from = @newfrom;
    }
    unless ($flags & OPpTRANS_DELETE || !@to) {
	pop @to while $#to and $to[$#to] == $to[$#to -1];
    }
    my($from, $to);
    $from = collapse(@from);
    $to = collapse(@to);
    $from .= "-" if $delhyphen;
    return ($from, $to);
}

sub tr_chr {
    my $x = shift;
    if ($x == ord "-") {
	return "\\-";
    } elsif ($x == ord "\\") {
	return "\\\\";
    } else {
	return chr $x;
    }
}

# XXX This doesn't yet handle all cases correctly either

sub tr_decode_utf8 {
    my($swash_hv, $flags) = @_;
    my %swash = $swash_hv->ARRAY;
    my $final = undef;
    $final = $swash{'FINAL'}->IV if exists $swash{'FINAL'};
    my $none = $swash{"NONE"}->IV;
    my $extra = $none + 1;
    my(@from, @delfrom, @to);
    my $line;
    foreach $line (split /\n/, $swash{'LIST'}->PV) {
	my($min, $max, $result) = split(/\t/, $line);
	$min = hex $min;
	if (length $max) {
	    $max = hex $max;
	} else {
	    $max = $min;
	}
	$result = hex $result;
	if ($result == $extra) {
	    push @delfrom, [$min, $max];
	} else {
	    push @from, [$min, $max];
	    push @to, [$result, $result + $max - $min];
	}
    }
    for my $i (0 .. $#from) {
	if ($from[$i][0] == ord '-') {
	    unshift @from, splice(@from, $i, 1);
	    unshift @to, splice(@to, $i, 1);
	    last;
	} elsif ($from[$i][1] == ord '-') {
	    $from[$i][1]--;
	    $to[$i][1]--;
	    unshift @from, ord '-';
	    unshift @to, ord '-';
	    last;
	}
    }
    for my $i (0 .. $#delfrom) {
	if ($delfrom[$i][0] == ord '-') {
	    push @delfrom, splice(@delfrom, $i, 1);
	    last;
	} elsif ($delfrom[$i][1] == ord '-') {
	    $delfrom[$i][1]--;
	    push @delfrom, ord '-';
	    last;
	}
    }
    if (defined $final and $to[$#to][1] != $final) {
	push @to, [$final, $final];
    }
    push @from, @delfrom;
    if ($flags & OPpTRANS_COMPLEMENT) {
	my @newfrom;
	my $next = 0;
	for my $i (0 .. $#from) {
	    push @newfrom, [$next, $from[$i][0] - 1];
	    $next = $from[$i][1] + 1;
	}
	@from = ();
	for my $range (@newfrom) {
	    if ($range->[0] <= $range->[1]) {
		push @from, $range;
	    }
	}
    }
    my($from, $to, $diff);
    for my $chunk (@from) {
	$diff = $chunk->[1] - $chunk->[0];
	if ($diff > 1) {
	    $from .= tr_chr($chunk->[0]) . "-" . tr_chr($chunk->[1]);
	} elsif ($diff == 1) {
	    $from .= tr_chr($chunk->[0]) . tr_chr($chunk->[1]);
	} else {
	    $from .= tr_chr($chunk->[0]);
	}
    }
    for my $chunk (@to) {
	$diff = $chunk->[1] - $chunk->[0];
	if ($diff > 1) {
	    $to .= tr_chr($chunk->[0]) . "-" . tr_chr($chunk->[1]);
	} elsif ($diff == 1) {
	    $to .= tr_chr($chunk->[0]) . tr_chr($chunk->[1]);
	} else {
	    $to .= tr_chr($chunk->[0]);
	}
    }
    #$final = sprintf("%04x", $final) if defined $final;
    #$none = sprintf("%04x", $none) if defined $none;
    #$extra = sprintf("%04x", $extra) if defined $extra;
    #print STDERR "final: $final\n none: $none\nextra: $extra\n";
    #print STDERR $swash{'LIST'}->PV;
    return (escape_str($from), escape_str($to));
}

sub pp_trans {
    my $self = shift;
    my($op, $cx, $morflags) = @_;
    my($from, $to);
    my $class = class($op);
    my $priv_flags = $op->private;
    if ($class eq "PVOP") {
	($from, $to) = tr_decode_byte($op->pv, $priv_flags);
    } elsif ($class eq "PADOP") {
	($from, $to)
	  = tr_decode_utf8($self->padval($op->padix)->RV, $priv_flags);
    } else { # class($op) eq "SVOP"
	($from, $to) = tr_decode_utf8($op->sv->RV, $priv_flags);
    }
    my $flags = "";
    $flags .= "c" if $priv_flags & OPpTRANS_COMPLEMENT;
    $flags .= "d" if $priv_flags & OPpTRANS_DELETE;
    $to = "" if $from eq $to and $flags eq "";
    $flags .= "s" if $priv_flags & OPpTRANS_SQUASH;
    $flags .= $morflags if defined $morflags;
    my $ret = $self->keyword("tr") . double_delim($from, $to) . $flags;
    if (my $targ = $op->targ) {
	return $self->maybe_parens($self->padname($targ) . " =~ $ret",
				   $cx, 20);
    }
    return $ret;
}

sub pp_transr { push @_, 'r'; goto &pp_trans }

sub re_dq_disambiguate {
    my ($first, $last) = @_;
    # Disambiguate "${foo}bar", "${foo}{bar}", "${foo}[1]"
    ($last =~ /^[A-Z\\\^\[\]_?]/ &&
	$first =~ s/([\$@])\^$/${1}{^}/)  # "${^}W" etc
	|| ($last =~ /^[{\[\w_]/ &&
	    $first =~ s/([\$@])([A-Za-z_]\w*)$/${1}{$2}/);
    return $first . $last;
}

# Like dq(), but different
sub re_dq {
    my $self = shift;
    my ($op) = @_;

    my $type = $op->name;
    if ($type eq "const") {
	return '$[' if $op->private & OPpCONST_ARYBASE;
	my $unbacked = re_unback($self->const_sv($op)->as_string);
	return re_uninterp(escape_re($unbacked));
    } elsif ($type eq "concat") {
	my $first = $self->re_dq($op->first);
	my $last  = $self->re_dq($op->last);
	return re_dq_disambiguate($first, $last);
    } elsif ($type eq "uc") {
	return '\U' . $self->re_dq($op->first->sibling) . '\E';
    } elsif ($type eq "lc") {
	return '\L' . $self->re_dq($op->first->sibling) . '\E';
    } elsif ($type eq "ucfirst") {
	return '\u' . $self->re_dq($op->first->sibling);
    } elsif ($type eq "lcfirst") {
	return '\l' . $self->re_dq($op->first->sibling);
    } elsif ($type eq "quotemeta") {
	return '\Q' . $self->re_dq($op->first->sibling) . '\E';
    } elsif ($type eq "fc") {
	return '\F' . $self->re_dq($op->first->sibling) . '\E';
    } elsif ($type eq "join") {
	return $self->deparse($op->last, 26); # was join($", @ary)
    } else {
	my $ret = $self->deparse($op, 26);
	$ret =~ s/^\$([(|)])\z/\${$1}/ # $( $| $) need braces
	or $ret =~ s/^\@([-+])\z/\@{$1}/; # @- @+ need braces
	return $ret;
    }
}

sub pure_string {
    my ($self, $op) = @_;
    return 0 if null $op;
    my $type = $op->name;

    if ($type eq 'const' || $type eq 'av2arylen') {
	return 1;
    }
    elsif ($type =~ /^(?:[ul]c(first)?|fc)$/ || $type eq 'quotemeta') {
	return $self->pure_string($op->first->sibling);
    }
    elsif ($type eq 'join') {
	my $join_op = $op->first->sibling;  # Skip pushmark
	return 0 unless $join_op->name eq 'null' && $join_op->targ == OP_RV2SV;

	my $gvop = $join_op->first;
	return 0 unless $gvop->name eq 'gvsv';
        return 0 unless '"' eq $self->gv_name($self->gv_or_padgv($gvop));

	return 0 unless ${$join_op->sibling} eq ${$op->last};
	return 0 unless $op->last->name =~ /^(?:[ah]slice|(?:rv2|pad)av)$/;
    }
    elsif ($type eq 'concat') {
	return $self->pure_string($op->first)
            && $self->pure_string($op->last);
    }
    elsif (is_scalar($op) || $type =~ /^[ah]elem$/) {
	return 1;
    }
    elsif ($type eq "null" and $op->can('first') and not null $op->first) {
        my $first = $op->first;

        return 1 if $first->name eq "multideref";
        return 1 if $first->name eq "aelemfast_lex";

        if (    $first->name eq "null"
            and $first->can('first')
	    and not null $first->first
            and $first->first->name eq "aelemfast"
	   )
        {
            return 1;
        }
    }

    return 0;
}

sub code_list {
    my ($self,$op,$cv) = @_;

    # localise stuff relating to the current sub
    $cv and
	local($self->{'curcv'}) = $cv,
	local($self->{'curcvlex'}),
	local(@$self{qw'curstash warnings hints hinthash curcop'})
	    = @$self{qw'curstash warnings hints hinthash curcop'};

    my $re;
    for ($op = $op->first->sibling; !null($op); $op = $op->sibling) {
	if ($op->name eq 'null' and $op->flags & OPf_SPECIAL) {
	    my $scope = $op->first;
	    # 0 context (last arg to scopeop) means statement context, so
	    # the contents of the block will not be wrapped in do{...}.
	    my $block = scopeop($scope->first->name eq "enter", $self,
				$scope, 0);
	    # next op is the source code of the block
	    $op = $op->sibling;
	    $re .= ($self->const_sv($op)->PV =~ m|^(\(\?\??\{)|)[0];
	    my $multiline = $block =~ /\n/;
	    $re .= $multiline ? "\n\t" : ' ';
	    $re .= $block;
	    $re .= $multiline ? "\n\b})" : " })";
	} else {
	    $re = re_dq_disambiguate($re, $self->re_dq($op));
	}
    }
    $re;
}

sub regcomp {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first;
    $kid = $kid->first if $kid->name eq "regcmaybe";
    $kid = $kid->first if $kid->name eq "regcreset";
    my $kname = $kid->name;
    if ($kname eq "null" and !null($kid->first)
	and $kid->first->name eq 'pushmark')
    {
	my $str = '';
	$kid = $kid->first->sibling;
	while (!null($kid)) {
	    my $first = $str;
	    my $last = $self->re_dq($kid);
	    $str = re_dq_disambiguate($first, $last);
	    $kid = $kid->sibling;
	}
	return $str, 1;
    }

    return ($self->re_dq($kid), 1)
	if $kname =~ /^(?:rv2|pad)av/ or $self->pure_string($kid);
    return ($self->deparse($kid, $cx), 0);
}

sub pp_regcomp {
    my ($self, $op, $cx) = @_;
    return (($self->regcomp($op, $cx, 0))[0]);
}

sub re_flags {
    my ($self, $op) = @_;
    my $flags = '';
    my $pmflags = $op->pmflags;
    if (!$pmflags) {
	my $re = $op->pmregexp;
	if ($$re) {
	    $pmflags = $re->compflags;
	}
    }
    $flags .= "g" if $pmflags & PMf_GLOBAL;
    $flags .= "i" if $pmflags & PMf_FOLD;
    $flags .= "m" if $pmflags & PMf_MULTILINE;
    $flags .= "o" if $pmflags & PMf_KEEP;
    $flags .= "s" if $pmflags & PMf_SINGLELINE;
    $flags .= "x" if $pmflags & PMf_EXTENDED;
    $flags .= "x" if $pmflags & PMf_EXTENDED_MORE;
    $flags .= "p" if $pmflags & PMf_KEEPCOPY;
    $flags .= "n" if $pmflags & PMf_NOCAPTURE;
    if (my $charset = $pmflags & PMf_CHARSET) {
	# Hardcoding this is fragile, but B does not yet export the
	# constants we need.
	$flags .= qw(d l u a aa)[$charset >> 7]
    }
    # The /d flag is indicated by 0; only show it if necessary.
    elsif ($self->{hinthash} and
	     $self->{hinthash}{reflags_charset}
	    || $self->{hinthash}{feature_unicode}
	or $self->{hints} & $feature::hint_mask
	  && ($self->{hints} & $feature::hint_mask)
	       != $feature::hint_mask
	  && $self->{hints} & $feature::hint_uni8bit
    ) {
	$flags .= 'd';
    }
    $flags;
}

# osmic acid -- see osmium tetroxide

my %matchwords;
map($matchwords{join "", sort split //, $_} = $_, 'cig', 'cog', 'cos', 'cogs',
    'cox', 'go', 'is', 'ism', 'iso', 'mig', 'mix', 'osmic', 'ox', 'sic',
    'sig', 'six', 'smog', 'so', 'soc', 'sog', 'xi', 'soup', 'soupmix');

# When deparsing a regular expression with code blocks, we have to look in
# various places to find the blocks.
#
# For qr/(?{...})/ without interpolation, the CV is under $qr->qr_anoncv
# and the code list (list of blocks and constants, maybe vars) is under
# $cv->ROOT->first->code_list:
#   ./perl -Ilib -MB -e 'use O "Concise", B::svref_2object(sub {qr/(?{die})/})->ROOT->first->first->sibling->pmregexp->qr_anoncv->object_2svref'
#
# For qr/$a(?{...})/ with interpolation, the code list is more accessible,
# under $pmop->code_list, but the $cv is something you have to dig for in
# the regcomp op’s kids:
#   ./perl -Ilib -mO=Concise -e 'qr/$a(?{die})/'
#
# For m// and split //, things are much simpler.  There is no CV.  The code
# list is under $pmop->code_list.

sub matchop {
    my $self = shift;
    my($op, $cx, $name, $delim) = @_;
    my $kid = $op->first;
    my ($binop, $var, $re) = ("", "", "");
    if ($op->flags & OPf_STACKED) {
	$binop = 1;
	$var = $self->deparse($kid, 20);
	$kid = $kid->sibling;
    }
           # not $name; $name will be 'm' for both match and split
    elsif ($op->name eq 'match' and my $targ = $op->targ) {
	$binop = 1;
	$var = $self->padname($targ);
    }
    my $quote = 1;
    my $pmflags = $op->pmflags;
    my $rhs_bound_to_defsv;
    my ($cv, $bregexp);
    my $have_kid = !null $kid;
    # Check for code blocks first
    if (not null my $code_list = $op->code_list) {
	$re = $self->code_list($code_list,
			       $op->name eq 'qr'
				   ? $self->padval(
				         $kid->first   # ex-list
					     ->first   #   pushmark
					     ->sibling #   entersub
					     ->first   #     ex-list
					     ->first   #       pushmark
					     ->sibling #       srefgen
					     ->first   #         ex-list
					     ->first   #           anoncode
					     ->targ
				     )
				   : undef);
    } elsif (${$bregexp = $op->pmregexp} && ${$cv = $bregexp->qr_anoncv}) {
	my $patop = $cv->ROOT      # leavesub
		       ->first     #   qr
		       ->code_list;#     list
	$re = $self->code_list($patop, $cv);
    } elsif (!$have_kid) {
	$re = re_uninterp(escape_re(re_unback($op->precomp)));
    } elsif ($kid->name ne 'regcomp') {
	carp("found ".$kid->name." where regcomp expected");
    } else {
	($re, $quote) = $self->regcomp($kid, 21);
    }
    if ($have_kid and $kid->name eq 'regcomp') {
	my $matchop = $kid->first;
	if ($matchop->name eq 'regcreset') {
	    $matchop = $matchop->first;
	}
	if ($matchop->name =~ /^(?:match|transr?|subst)\z/
	   && $matchop->flags & OPf_SPECIAL) {
	    $rhs_bound_to_defsv = 1;
	}
    }
    my $flags = "";
    $flags .= "c" if $pmflags & PMf_CONTINUE;
    $flags .= $self->re_flags($op);
    $flags = join '', sort split //, $flags;
    $flags = $matchwords{$flags} if $matchwords{$flags};
    if ($pmflags & PMf_ONCE) { # only one kind of delimiter works here
	$re =~ s/\?/\\?/g;
	$re = $self->keyword("m") . "?$re?";     # explicit 'm' is required
    } elsif ($quote) {
	$re = single_delim($name, $delim, $re, $self);
    }
    $re = $re . $flags if $quote;
    if ($binop) {
	return
	 $self->maybe_parens(
	  $rhs_bound_to_defsv
	   ? "$var =~ (\$_ =~ $re)"
	   : "$var =~ $re",
	  $cx, 20
	 );
    } else {
	return $re;
    }
}

sub pp_match { matchop(@_, "m", "/") }
sub pp_pushre { matchop(@_, "m", "/") }
sub pp_qr { matchop(@_, "qr", "") }

sub pp_runcv { unop(@_, "__SUB__"); }

sub pp_split {
    maybe_targmy(@_, \&split);
}
sub split {
    my $self = shift;
    my($op, $cx) = @_;
    my($kid, @exprs, $ary, $expr);
    $kid = $op->first;

    # For our kid (an OP_PUSHRE), pmreplroot is never actually the
    # root of a replacement; it's either empty, or abused to point to
    # the GV for an array we split into (an optimization to save
    # assignment overhead). Depending on whether we're using ithreads,
    # this OP* holds either a GV* or a PADOFFSET. Luckily, B.xs
    # figures out for us which it is.
    my $replroot = $kid->pmreplroot;
    my $gv = 0;
    my $stacked = $op->flags & OPf_STACKED;
    if (ref($replroot) eq "B::GV") {
	$gv = $replroot;
    } elsif (!ref($replroot) and $replroot > 0) {
	$gv = $self->padval($replroot);
    } elsif ($kid->targ) {
	$ary = $self->padname($kid->targ)
    } elsif ($stacked) {
	$ary = $self->deparse($op->last, 7);
    }
    $ary = $self->maybe_local(@_,
			      $self->stash_variable('@',
						     $self->gv_name($gv),
						     $cx))
	if $gv;

    # Skip the last kid when OPf_STACKED is set, since it is the array
    # on the left.
    for (; !null($stacked ? $kid->sibling : $kid); $kid = $kid->sibling) {
	push @exprs, $self->deparse($kid, 6);
    }

    # handle special case of split(), and split(' ') that compiles to /\s+/
    # Under 5.10, the reflags may be undef if the split regexp isn't a constant
    # Under 5.17.5-5.17.9, the special flag is on split itself.
    $kid = $op->first;
    if ( $op->flags & OPf_SPECIAL
         or (
            $kid->flags & OPf_SPECIAL
            and ( $] < 5.009 ? $kid->pmflags & PMf_SKIPWHITE()
                             : ($kid->reflags || 0) & RXf_SKIPWHITE()
            )
         )
    ) {
	$exprs[0] = "' '";
    }

    $expr = "split(" . join(", ", @exprs) . ")";
    if ($ary) {
	return $self->maybe_parens("$ary = $expr", $cx, 7);
    } else {
	return $expr;
    }
}

# oxime -- any of various compounds obtained chiefly by the action of
# hydroxylamine on aldehydes and ketones and characterized by the
# bivalent grouping C=NOH [Webster's Tenth]

my %substwords;
map($substwords{join "", sort split //, $_} = $_, 'ego', 'egoism', 'em',
    'es', 'ex', 'exes', 'gee', 'go', 'goes', 'ie', 'ism', 'iso', 'me',
    'meese', 'meso', 'mig', 'mix', 'os', 'ox', 'oxime', 'see', 'seem',
    'seg', 'sex', 'sig', 'six', 'smog', 'sog', 'some', 'xi', 'rogue',
    'sir', 'rise', 'smore', 'more', 'seer', 'rome', 'gore', 'grim', 'grime',
    'or', 'rose', 'rosie');

sub pp_subst {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first;
    my($binop, $var, $re, $repl) = ("", "", "", "");
    if ($op->flags & OPf_STACKED) {
	$binop = 1;
	$var = $self->deparse($kid, 20);
	$kid = $kid->sibling;
    }
    elsif (my $targ = $op->targ) {
	$binop = 1;
	$var = $self->padname($targ);
    }
    my $flags = "";
    my $pmflags = $op->pmflags;
    if (null($op->pmreplroot)) {
	$repl = $kid;
	$kid = $kid->sibling;
    } else {
	$repl = $op->pmreplroot->first; # skip substcont
    }
    while ($repl->name eq "entereval") {
	    $repl = $repl->first;
	    $flags .= "e";
    }
    {
	local $self->{in_subst_repl} = 1;
	if ($pmflags & PMf_EVAL) {
	    $repl = $self->deparse($repl->first, 0);
	} else {
	    $repl = $self->dq($repl);	
	}
    }
    if (not null my $code_list = $op->code_list) {
	$re = $self->code_list($code_list);
    } elsif (null $kid) {
	$re = re_uninterp(escape_re(re_unback($op->precomp)));
    } else {
	($re) = $self->regcomp($kid, 1);
    }
    $flags .= "r" if $pmflags & PMf_NONDESTRUCT;
    $flags .= "e" if $pmflags & PMf_EVAL;
    $flags .= $self->re_flags($op);
    $flags = join '', sort split //, $flags;
    $flags = $substwords{$flags} if $substwords{$flags};
    my $core_s = $self->keyword("s"); # maybe CORE::s
    if ($binop) {
	return $self->maybe_parens("$var =~ $core_s"
				   . double_delim($re, $repl) . $flags,
				   $cx, 20);
    } else {
	return "$core_s". double_delim($re, $repl) . $flags;	
    }
}

sub is_lexical_subs {
    my (@ops) = shift;
    for my $op (@ops) {
        return 0 if $op->name !~ /\A(?:introcv|clonecv)\z/;
    }
    return 1;
}

# Pretend these two ops do not exist.  The perl parser adds them to the
# beginning of any block containing my-sub declarations, whereas we handle
# the subs in pad_subs and next_todo.
*pp_clonecv = *pp_introcv;
sub pp_introcv {
    my $self = shift;
    my($op, $cx) = @_;
    # For now, deparsing doesn't worry about the distinction between introcv
    # and clonecv, so pretend this op doesn't exist:
    return '';
}

sub pp_padcv {
    my $self = shift;
    my($op, $cx) = @_;
    return $self->padany($op);
}

my %lvref_funnies = (
    OPpLVREF_SV, => '$',
    OPpLVREF_AV, => '@',
    OPpLVREF_HV, => '%',
    OPpLVREF_CV, => '&',
);

sub pp_refassign {
    my ($self, $op, $cx) = @_;
    my $left;
    if ($op->private & OPpLVREF_ELEM) {
	$left = $op->first->sibling;
	$left = maybe_local(@_, elem($self, $left, undef,
				     $left->targ == OP_AELEM
					? qw([ ] padav)
					: qw({ } padhv)));
    } elsif ($op->flags & OPf_STACKED) {
	$left = maybe_local(@_,
			    $lvref_funnies{$op->private & OPpLVREF_TYPE}
			  . $self->deparse($op->first->sibling));
    } else {
	$left = &pp_padsv;
    }
    my $right = $self->deparse_binop_right($op, $op->first, 7);
    return $self->maybe_parens("\\$left = $right", $cx, 7);
}

sub pp_lvref {
    my ($self, $op, $cx) = @_;
    my $code;
    if ($op->private & OPpLVREF_ELEM) {
	$code = $op->first->name =~ /av\z/ ? &pp_aelem : &pp_helem;
    } elsif ($op->flags & OPf_STACKED) {
	$code = maybe_local(@_,
			    $lvref_funnies{$op->private & OPpLVREF_TYPE}
			  . $self->deparse($op->first));
    } else {
	$code = &pp_padsv;
    }
    "\\$code";
}

sub pp_lvrefslice {
    my ($self, $op, $cx) = @_;
    '\\' . ($op->last->name =~ /av\z/ ? &pp_aslice : &pp_hslice);
}

sub pp_lvavref {
    my ($self, $op, $cx) = @_;
    '\\(' . ($op->flags & OPf_STACKED
		? maybe_local(@_, rv2x(@_, "\@"))
		: &pp_padsv)  . ')'
}

1;
__END__

#line 6287