/usr/local/CPAN/Introspector/B/IntrospectorDeparse.pm


# B::IntrospectorDeparse.pm
# Copyright (c) 1998, 1999, 2000 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.

# Modified by Michael DuPont
# see lines marked with mdupont todo

# this code is a modified version from conway, modified by mdupont 
#################################################################
# Changes by    : James Michael DuPont
# Status        :  to update
# Generation    :  second Generation
# Category      :  Perl Meta Programmming
# 
#
# LICENCE STATEMENT
#    This file is part of the GCC XML Node Introspector Project
#    Copyright (C) 2001-2002  James Michael DuPont
#
#    This program is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 of the License, or
#    (at your option) any later version.     
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.     
# 
#    You should have received a copy of the GNU General Public License
#    along with this program; if not, write to the Free Software
#    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#    Or see http://www.gnu.org/licenses/gpl.txt
###############################################################################

package B::IntrospectorDeparse;
use Carp 'cluck', 'croak';
use B qw(class main_root main_start main_cv svref_2object opnumber
	 OPf_WANT OPf_WANT_VOID OPf_WANT_SCALAR OPf_WANT_LIST
	 OPf_KIDS OPf_REF OPf_STACKED OPf_SPECIAL
	 OPpLVAL_INTRO OPpENTERSUB_AMPER OPpSLICE OPpCONST_BARE
	 OPpTRANS_SQUASH OPpTRANS_DELETE OPpTRANS_COMPLEMENT OPpTARGET_MY
	 SVf_IOK SVf_NOK SVf_ROK SVf_POK
         CVf_METHOD CVf_LOCKED CVf_LVALUE
	 PMf_KEEP PMf_GLOBAL PMf_CONTINUE PMf_EVAL PMf_ONCE
	 PMf_MULTILINE PMf_SINGLELINE PMf_FOLD PMf_EXTENDED);
use Data::Dumper;
$VERSION = 0.60;
use strict;

# Changes between 0.50 and 0.51:
# - fixed nulled leave with live enter in sort { }
# - fixed reference constants (\"str")
# - handle empty programs gracefully
# - handle infinte 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_THREADS)
# - 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 attribues was added
# - some warnings fixed
# - separate recognition of constant subs
# - rewrote continue block handling, now recoginizing for loops
# - added more control of expanding control structures

# Todo:
# - finish tr/// changes
# - add option for even more parens (generalize \&foo change)
# - {} around variables in strings ("${var}letters")
#   base/lex.t 25-27
#   comp/term.t 11
# - left/right context
# - recognize `use utf8', `use integer', etc
# - treat top-level block specially for incremental output
# - interpret high bit chars in string as utf8 \x{...} (when?)
# - 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'?
# - include values of variables (e.g. set in BEGIN)
# - coordinate with Data::Dumper (both directions? see previous)
# - version using op_next instead of op_first/sibling?
# - avoid string copies (pass arrays, one big join?)
# - auto-apply `-u'?
# - -uPackage:: descend recursively?
# - here-docs?
# - <DATA>?

# Tests that will always fail:
# comp/redef.t -- all (redefinition happens at compile time)

# Object fields (were globals):
#
# 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
#
# curstash:
# name of the current package for deparsed code
#
# subs_todo:
# array of [cop_seq, GV, is_format?] for subs and formats we still
# want to deparse
#
# 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)
#
# 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             statement level

# 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

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

sub todo {
    my $self = shift;
    my($gv, $cv, $is_form) = @_;
    my $seq;
    if (!null($cv->START) and is_state($cv->START)) {
	$seq = $cv->START->cop_seq;
    } else {
	$seq = 0;
    }
    push @{$self->{'subs_todo'}}, [$seq, $gv, $is_form];
}

sub next_todo {
    my $self = shift;
    my $ent = shift @{$self->{'subs_todo'}};
    my $name = $self->gv_name($ent->[1]);
    if ($ent->[2]) {
	return "format $name =\n"
	    . $self->deparse_format($ent->[1]->FORM). "\n";
    } else {
	return "sub $name " . $self->deparse_sub($ent->[1]->CV);
    }
}

sub walk_tree {
    my($op, $sub) = @_;
    $sub->($op);
    if ($op->flags & OPf_KIDS) {
	my $kid;
	for ($kid = $op->first; not null $kid; $kid = $kid->sibling) {
	    walk_tree($kid, $sub);
	}
    }
}

sub walk_sub {
    my $self = shift;
    my $cv = shift;
    my $op = $cv->ROOT;
    $op = shift if null $op;
    return if !$op or null $op;
    walk_tree($op, sub {
	my $op = shift;
	if ($op->name eq "gv") {
	    my $gv = $self->gv_or_padgv($op);

	    return if not $gv; # mdupont

	    if ($op->next->name eq "entersub") {
		
		return if $self->{'subs_done'}{$$gv}++;
		return if class($gv->CV) eq "SPECIAL";
		$self->todo($gv, $gv->CV, 0);
		$self->walk_sub($gv->CV);
	    } elsif ($op->next->name eq "enterwrite"
		     or ($op->next->name eq "rv2gv"
			 and $op->next->next->name eq "enterwrite")) {
		return if $self->{'forms_done'}{$$gv}++;
		return if class($gv->FORM) eq "SPECIAL";
		$self->todo($gv, $gv->FORM, 1);
		$self->walk_sub($gv->FORM);
	    }
	}
    });
}

sub stash_subs {
    my $self = shift;
    my $pack = shift;
    my(%stash, @ret);
    { no strict 'refs'; %stash = svref_2object(\%{$pack . "::"})->ARRAY }
    if ($pack eq "main") {
	$pack = "";
    } else {
	$pack = $pack . "::";
    }
    my($key, $val);
    while (($key, $val) = each %stash) {
	my $class = class($val);
	if ($class eq "PV") {
	    # Just a prototype
	    push @{$self->{'protos_todo'}}, [$pack . $key, $val->PV];
	} elsif ($class eq "IV") {
	    # Just a name
	    push @{$self->{'protos_todo'}}, [$pack . $key, undef];	    
	} elsif ($class eq "GV") {
	    if (class($val->CV) ne "SPECIAL") {
		next if $self->{'subs_done'}{$$val}++;
		$self->todo($val, $val->CV, 0);
		$self->walk_sub($val->CV);
	    }
	    if (class($val->FORM) ne "SPECIAL") {
		next if $self->{'forms_done'}{$$val}++;
		$self->todo($val, $val->FORM, 1);
		$self->walk_sub($val->FORM);
	    }
	}
    }
}

sub print_protos {
    my $self = shift;
    my $ar;
    my @ret;
    foreach $ar (@{$self->{'protos_todo'}}) {
	my $proto = (defined $ar->[1] ? " (". $ar->[1] . ")" : "");
	push @ret, "sub " . $ar->[0] .  "$proto;\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->{'subs_todo'} = [];
    $self->{'curstash'} = "main";
    $self->{'cuddle'} = "\n";
    $self->{'indent_size'} = 4;
    $self->{'use_tabs'} = 0;
    $self->{'expand'} = 0;
    $self->{'unquote'} = 0;
    $self->{'linenums'} = 0;
    $self->{'parens'} = 0;
    $self->{'ex_const'} = "'???'";
    while (my $arg = shift @_) {
	if (substr($arg, 0, 2) eq "-u") {
	    $self->stash_subs(substr($arg, 2));
	} elsif ($arg eq "-p") {
	    $self->{'parens'} = 1;
	} elsif ($arg eq "-l") {
	    $self->{'linenums'} = 1;
	} elsif ($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;
}


sub coderef2text {
    my $self = shift;
    my $sub = shift;
    croak "Usage: ->coderef2text(CODEREF)" unless ref($sub) eq "CODE";
    return $self->indent($self->deparse_sub(svref_2object($sub)));
}

sub deparse {
    my $self = shift;
    my($op, $cx) = @_;
#    cluck if class($op) eq "NULL";
#    cluck unless $op;
#    return $self->$ {\("pp_" . $op->name)}($op, $cx);
    my $meth = "pp_" . $op->name;
    return $self->$meth($op, $cx);
}

sub indent {
    my $self = shift;
    my $txt = shift;
    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 (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 deparse_sub {
    my $self = shift;
    my $cv = shift;
    my $proto = "";
    if ($cv->FLAGS & SVf_POK) {
	$proto = "(". $cv->PV . ") ";
    }
    if ($cv->CvFLAGS & (CVf_METHOD|CVf_LOCKED|CVf_LVALUE)) {
        $proto .= ": ";
        $proto .= "lvalue " if $cv->CvFLAGS & CVf_LVALUE;
        $proto .= "locked " if $cv->CvFLAGS & CVf_LOCKED;
        $proto .= "method " if $cv->CvFLAGS & CVf_METHOD;
    }

    local($self->{'curcv'}) = $cv;
    local($self->{'curstash'}) = $self->{'curstash'};
    if (not null $cv->ROOT) {
	# skip leavesub
	return $proto . "{\n\t" . 
	    $self->deparse($cv->ROOT->first, 0) . "\n\b}\n"; 
    } else { # XSUB?
	return $proto  . "{}\n";
    }
}

sub deparse_format {
    my $self = shift;
    my $form = shift;
    my @text;
    local($self->{'curcv'}) = $form;
    local($self->{'curstash'}) = $self->{'curstash'};
    my $op = $form->ROOT;
    my $kid;
    $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, $self->const_sv($kid)->PV;
	$kid = $kid->sibling;
	for (; not null $kid; $kid = $kid->sibling) {
	    push @exprs, $self->deparse($kid, 0);
	}
	push @text, join(", ", @exprs)."\n" if @exprs;
	$op = $op->sibling;
    }
    return join("", @text) . ".";
}

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")
		 ));
}

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 $self->{'parens'}) {
	return "$name(" . $self->deparse($kid, 1) . ")";
    } else {
	$kid = $self->deparse($kid, 16);
	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 maybe_local {
    my $self = shift;
    my($op, $cx, $text) = @_;
    if ($op->private & OPpLVAL_INTRO and not $self->{'avoid_local'}{$$op}) {
        if (want_scalar($op)) {
	    return "local $text";
	} else {
	    return $self->maybe_parens_func("local", $text, $cx, 16);
	}
    } else {
	return $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->ARRAY)[0]->ARRAY)[$targ];
}

sub maybe_my {
    my $self = shift;
    my($op, $cx, $text) = @_;
    if ($op->private & OPpLVAL_INTRO and not $self->{'avoid_local'}{$$op}) {
	if (want_scalar($op)) {
	    return "my $text";
	} else {
	    return $self->maybe_parens_func("my", $text, $cx, 16);
	}
    } else {
	return $text;
    }
}

# The following OPs don't have functions:

# pp_padany -- does not exist after parsing
# pp_rcatline -- does not exist

sub pp_enter { # see also leave
    cluck "unexpected OP_ENTER";
    return "XXX";
}

sub pp_pushmark { # see also list
    cluck "unexpected OP_PUSHMARK";
    return "XXX";
}

sub pp_leavesub { # see also deparse_sub
    cluck "unexpected OP_LEAVESUB";
    return "XXX";
}

sub pp_leavewrite { # see also deparse_format
    cluck "unexpected OP_LEAVEWRITE";
    return "XXX";
}

sub pp_method { # see also entersub
    cluck "unexpected OP_METHOD";
    return "XXX";
}

sub pp_regcmaybe { # see also regcomp
    cluck "unexpected OP_REGCMAYBE";
    return "XXX";
}

sub pp_regcreset { # see also regcomp
    cluck "unexpected OP_REGCRESET";
    return "XXX";
}

sub pp_substcont { # see also subst
    cluck "unexpected OP_SUBSTCONT";
    return "XXX";
}

sub pp_grepstart { # see also grepwhile
    cluck "unexpected OP_GREPSTART";
    return "XXX";
}

sub pp_mapstart { # see also mapwhile
    cluck "unexpected OP_MAPSTART";
    return "XXX";
}

sub pp_flip { # see also flop
    cluck "unexpected OP_FLIP";
    return "XXX";
}

sub pp_iter { # see also leaveloop
    cluck "unexpected OP_ITER";
    return "XXX";
}

sub pp_enteriter { # see also leaveloop
    cluck "unexpected OP_ENTERITER";
    return "XXX";
}

sub pp_enterloop { # see also leaveloop
    cluck "unexpected OP_ENTERLOOP";
    return "XXX";
}

sub pp_leaveeval { # see also entereval
    cluck "unexpected OP_LEAVEEVAL";
    return "XXX";
}

sub pp_entertry { # see also leavetry
    cluck "unexpected OP_ENTERTRY";
    return "XXX";
}

sub lineseq {
    my $self = shift;
    my(@ops) = @_;
    my($expr, @exprs);
    for (my $i = 0; $i < @ops; $i++) {
	$expr = "";
	if (is_state $ops[$i]) {
	    $expr = $self->deparse($ops[$i], 0);
	    $i++;
	    last if $i > $#ops;
	}
	if (!is_state $ops[$i] and $ops[$i+1] and !null($ops[$i+1]) and
	    $ops[$i+1]->name eq "leaveloop" and $self->{'expand'} < 3)
	{
	    push @exprs, $expr . $self->for_loop($ops[$i], 0);
	    $i++;
	    next;
	}
	$expr .= $self->deparse($ops[$i], 0);
	push @exprs, $expr if length $expr;
    }
    return join(";\n", @exprs);
}

sub scopeop {
    my($real_block, $self, $op, $cx) = @_;
    my $kid;
    my @kids;
    local($self->{'curstash'}) = $self->{'curstash'} 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") {
		$name = "while";
	    } elsif ($name eq "or") {
		$name = "until";
	    } else { # no conditional -> while 1 or until 0
		return $self->deparse($top->first, 1) . " 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)
	return "do { " . $self->lineseq(@kids) . " }";
    } else {
	return $self->lineseq(@kids) . ";";
    }
}

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

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

sub gv_name {
    my $self = shift;
    my $gv = shift;
    my $stash = $gv->STASH->NAME;
    my $name = $gv->SAFENAME;
    if ($stash eq $self->{'curstash'} or $globalnames{$name}
	or $name =~ /^[^A-Za-z_]/)
    {
	$stash = "";
    } else {
	$stash = $stash . "::";
    }
    if ($name =~ /^\^../) {
        $name = "{$name}";       # ${^WARNING_BITS} etc
    }
    return $stash . $name;
}

# Notice how subs and formats are inserted between statements here
sub pp_nextstate {
    my $self = shift;
    my($op, $cx) = @_;
    my @text;
    @text = $op->label . ": " if $op->label;
    my $seq = $op->cop_seq;
    while (scalar(@{$self->{'subs_todo'}})
	   and $seq > $self->{'subs_todo'}[0][0]) {
	push @text, $self->next_todo;
    }
    my $stash = $op->stashpv;
    if ($stash ne $self->{'curstash'}) {
	push @text, "package $stash;\n";
	$self->{'curstash'} = $stash;
    }
    if ($self->{'linenums'}) {
	push @text, "\f#line " . $op->line . 
	  ' "' . $op->file, qq'"\n';
    }
    return join("", @text);
}

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

sub pp_unstack { return "" } # see also leaveloop

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

sub pp_stub { baseop(@_, "()") }
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" : "$name$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) }

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) {
	$self->pfixop($op, $cx, "not ", 4);
    } else {
	$self->pfixop($op, $cx, "!", 21);	
    }
}

sub unop {
    my $self = shift;
    my($op, $cx, $name) = @_;
    my $kid;
    if ($op->flags & OPf_KIDS) {
	$kid = $op->first;
	return $self->maybe_parens_unop($name, $kid, $cx);
    } else {
	return $name .  ($op->flags & OPf_SPECIAL ? "()" : "");       
    }
}

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") }
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 { 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 { unop(@_, "do") }
sub pp_entereval { unop(@_, "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_exists {
    my $self = shift;
    my($op, $cx) = @_;
    return $self->maybe_parens_func("exists", $self->pp_helem($op->first, 16),
				    $cx, 16);
}

sub pp_delete {
    my $self = shift;
    my($op, $cx) = @_;
    my $arg;
    if ($op->private & OPpSLICE) {
	return $self->maybe_parens_func("delete",
					$self->pp_hslice($op->first, 16),
					$cx, 16);
    } else {
	return $self->maybe_parens_func("delete",
					$self->pp_helem($op->first, 16),
					$cx, 16);
    }
}

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

    if (class($op) eq "UNOP" and $op->first->name eq "const"
	and $op->first->private & OPpCONST_BARE)
    {
	my $name = $self->const_sv($op->first)->PV;
	$name =~ s[/][::]g;
	$name =~ s/\.pm//g;
	return "require($name)";
    } else {	
	$self->unop($op, $cx, "require");
    }
}

sub pp_scalar { 
    my $self = shift;
    my($op, $cv) = @_;
    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;
#    cluck "curcv was undef" unless $self->{curcv};
    return undef unless $self->{curcv}; # mdupont changed TODO
    return (($self->{'curcv'}->PADLIST->ARRAY)[1]->ARRAY)[$targ];
}

sub pp_refgen {
    my $self = shift;	
    my($op, $cx) = @_;
    my $kid = $op->first;
    if ($kid->name eq "null") {
	$kid = $kid->first;
	if ($kid->name eq "anonlist" || $kid->name eq "anonhash") {
	    my($pre, $post) = @{{"anonlist" => ["[","]"],
				 "anonhash" => ["{","}"]}->{$kid->name}};
	    my($expr, @exprs);
	    $kid = $kid->first->sibling; # skip pushmark
	    for (; !null($kid); $kid = $kid->sibling) {
		$expr = $self->deparse($kid, 6);
		push @exprs, $expr;
	    }
	    return $pre . join(", ", @exprs) . $post;
	} elsif (!null($kid->sibling) and 
		 $kid->sibling->name eq "anoncode") {
	    return "sub " .
		$self->deparse_sub($self->padval($kid->sibling->targ));
	} elsif ($kid->name eq "pushmark") {
            my $sib_name = $kid->sibling->name;
            if ($sib_name =~ /^(pad|rv2)[ah]v$/
                and not $kid->sibling->flags & OPf_REF)
            {
                # The @a in \(@a) isn't in ref context, but only when the
                # parens are there.
                return "\\(" . $self->deparse($kid->sibling, 1) . ")";
            } elsif ($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";
            }
        }
    }
    $self->pfixop($op, $cx, "\\", 20);
}

sub pp_srefgen { pp_refgen(@_) }

sub pp_readline {
    my $self = shift;
    my($op, $cx) = @_;
    my $kid = $op->first;
    $kid = $kid->first if $kid->name eq "rv2gv"; # <$fh>
    return "<" . $self->deparse($kid, 1) . ">";
}

# 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 loopex {
    my $self = shift;
    my ($op, $cx, $name) = @_;
    if (class($op) eq "PVOP") {
	return "$name " . $op->pv;
    } elsif (class($op) eq "OP") {
	return $name;
    } elsif (class($op) eq "UNOP") {
	# Note -- loop exits are actually exempt from the
	# looks-like-a-func rule, but a few extra parens won't hurt
	return $self->maybe_parens_unop($name, $op->first, $cx);
    }
}

sub pp_last { loopex(@_, "last") }
sub pp_next { loopex(@_, "next") }
sub pp_redo { loopex(@_, "redo") }
sub pp_goto { loopex(@_, "goto") }
sub pp_dump { loopex(@_, "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(); for the sake of clarity, give'em all parens
	return $self->maybe_parens_unop($name, $op->first, $cx);
    } elsif (class($op) eq "SVOP") {
	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(@_, "-r") }
sub pp_fteexec { ftst(@_, "-r") }
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

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,
	     'bit_or' => 12, 'bit_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,
	      'add=' => 7, 'i_add=' => 7,
	      'subtract=' => 7, 'i_subtract=' => 7,
	      'concat=' => 7,
	      'left_shift=' => 7, 'right_shift=' => 7,
	      'bit_and=' => 7,
	      'bit_or=' => 7, 'bit_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);
    }
    $left = $self->deparse_binop_left($op, $left, $prec);
    $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) }

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 { 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 { binop(@_, "cmp", 14) }

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

# `.' 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);
}

# `x' is weird when the left arg is a list
sub pp_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
	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 {
	$left = $self->deparse_binop_left($op, $left, $prec);
    }
    $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 = $op->first->sibling;
    if ($cx == 0 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 == 0 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") }

# 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 listop {
    my $self = shift;
    my($op, $cx, $name) = @_;
    my(@exprs);
    my $parens = ($cx >= 5) || $self->{'parens'};
    my $kid = $op->first->sibling;
    return $name if null $kid;
    my $first = $self->deparse($kid, 6);
    $first = "+$first" if not $parens and substr($first, 0, 1) eq "(";
    push @exprs, $first;
    $kid = $kid->sibling;
    for (; !null($kid); $kid = $kid->sibling) {
	push @exprs, $self->deparse($kid, 6);
    }
    if ($parens) {
	return "$name(" . join(", ", @exprs) . ")";
    } else {
	return "$name " . join(", ", @exprs);
    }
}

sub pp_bless { listop(@_, "bless") }
sub pp_atan2 { maybe_targmy(@_, \&listop, "atan2") }
sub pp_substr { maybe_local(@_, listop(@_, "substr")) }
sub pp_vec { 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") }
# Actually, return is exempt from the LLAFR (see examples in this very
# module!), but for consistency's sake, ignore that fact
sub pp_return { listop(@_, "return") }
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(@_, "sockpair") }
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(@_, \&listop, "system") }
sub pp_exec { maybe_targmy(@_, \&listop, "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 $text = $self->dq($op->first->sibling);  # skip pushmark
    if ($text =~ /^\$?(\w|::|\`)+$/ # could look like a readline
	or $text =~ /[<>]/) { 
	return 'glob(' . single_delim('qq', '"', $text) . ')';
    } else {
	return '<' . $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);
    if ($parens) {
	return "truncate($fh, $len)";
    } else {
	return "truncate $fh, $len";
    }
}

sub indirop {
    my $self = shift;
    my($op, $cx, $name) = @_;
    my($expr, @exprs);
    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) . "}";
	} else {
	    $indir = $self->deparse($indir, 24);
	}
	$indir = $indir . " ";
	$kid = $kid->sibling;
    }
    for (; !null($kid); $kid = $kid->sibling) {
	$expr = $self->deparse($kid, 6);
	push @exprs, $expr;
    }
    return $self->maybe_parens_func($name, $indir . join(", ", @exprs),
				    $cx, 5);
}

sub pp_prtf { indirop(@_, "printf") }
sub pp_print { indirop(@_, "print") }
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) . ", ";
    }
    $kid = $kid->sibling;
    for (; !null($kid); $kid = $kid->sibling) {
	$expr = $self->deparse($kid, 6);
	push @exprs, $expr if $expr;
    }
    return $self->maybe_parens_func($name, $code . join(", ", @exprs), $cx, 5);
}

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

sub pp_list {
    my $self = shift;
    my($op, $cx) = @_;
    my($expr, @exprs);
    my $kid = $op->first->sibling; # skip pushmark
    my $lop;
    my $local = "either"; # could be local(...) or my(...)
    for ($lop = $kid; !null($lop); $lop = $lop->sibling) {
	# This assumes that no other private flags equal 128, and that
	# OPs that store things other than flags in their op_private,
	# like OP_AELEMFAST, won't be immediate children of a list.
	unless ($lop->private & OPpLVAL_INTRO or $lop->name eq "undef")
	{
	    $local = ""; # or not
	    last;
	}
	if ($lop->name =~ /^pad[ash]v$/) { # my()
	    ($local = "", last) if $local eq "local";
	    $local = "my";
	} elsif ($lop->name ne "undef") { # local()
	    ($local = "", last) if $local eq "my";
	    $local = "local";
	}
    }
    $local = "" if $local eq "either"; # no point if it's all undefs
    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 == 0 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, 8);
	$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 $head = "if ($cond) {\n\t$true\n\b}";
    my @elsifs;
    while (!null($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
	$newcond = $self->deparse($newcond, 1);
	$newtrue = $self->deparse($newtrue, 0);
	push @elsifs, "elsif ($newcond) {\n\t$newtrue\n\b}";
    }
    if (!null($false)) {	    
	$false = $cuddle . "else {\n\t" .
	  $self->deparse($false, 0) . "\n\b}\cK";
    } else {
	$false = "\cK";
    }
    return $head . join($cuddle, "", @elsifs) . $false; 
}

sub loop_common {
    my $self = shift;
    my($op, $cx, $init) = @_;
    my $enter = $op->first;
    my $kid = $enter->sibling;
    local($self->{'curstash'}) = $self->{'curstash'};
    my $head = "";
    my $bare = 0;
    my $body;
    my $cond = undef;
    if ($kid->name eq "lineseq") { # bare or infinite loop 
	if (is_state $kid->last) { # infinite
	    $head = "for (;;) "; # shorter than while (1)
	    $cond = "";
	} else {
	    $bare = 1;
	}
	$body = $kid;
    } elsif ($enter->name eq "enteriter") { # foreach
	my $ary = $enter->first->sibling; # first was pushmark
	my $var = $ary->sibling;
	if ($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 $var) {
	    if ($enter->flags & OPf_SPECIAL) { # thread special var
		$var = $self->pp_threadsv($enter, 1);
	    } else { # regular my() variable
		$var = $self->pp_padsv($enter, 1);
		if ($self->padname_sv($enter->targ)->IVX ==
		    $kid->first->first->sibling->last->cop_seq)
		{
		    # If the scope of this variable closes at the last
		    # statement of the loop, it must have been
		    # declared here.
		    $var = "my " . $var;
		}
	    }
	} elsif ($var->name eq "rv2gv") {
	    $var = $self->pp_rv2sv($var, 1);
	} elsif ($var->name eq "gv") {
	    $var = "\$" . $self->deparse($var, 1);
	}
	$head = "foreach $var ($ary) ";
	$body = $kid->first->first->sibling; # skip OP_AND and OP_ITER
    } elsif ($kid->name eq "null") { # while/until
	$kid = $kid->first;
	my $name = {"and" => "while", "or" => "until"}->{$kid->name};
	$cond = $self->deparse($kid->first, 1);
	$head = "$name ($cond) ";
	$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 penultimate child, except
    # in a bare loop, when it will point to the leaveloop. When neither of
    # these conditions hold, then the third-to-last child in the continue
    # block (or the last in a bare loop).
    my $cont_start = $enter->nextop;
    my $cont;
    if ($$cont_start != $$op and $ {$cont_start->sibling} != $ {$body->last}) {
	if ($bare) {
	    $cont = $body->last;
	} else {
	    $cont = $body->first;
	    while (!null($cont->sibling->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(@states);
	if (defined $cond and not is_scope $cont and $self->{'expand'} < 3) {
	    $head = "for ($init; $cond; " . $self->deparse($cont, 1) .") ";
	    $cont = "\cK";
	} else {
	    $cont = $cuddle . "continue {\n\t" .
	      $self->deparse($cont, 0) . "\n\b}\cK";
	}
    } else {
	$cont = "\cK";
	$body = $self->deparse($body, 0);
    }
    return $head . "{\n\t" . $body . "\n\b}" . $cont;
}

sub pp_leaveloop { loop_common(@_, "") }

sub for_loop {
    my $self = shift;
    my($op, $cx) = @_;
    my $init = $self->deparse($op, 1);
    return $self->loop_common($op->sibling, $cx, $init);
}

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

BEGIN { eval "sub OP_CONST () {" . opnumber("const") . "}" }
BEGIN { eval "sub OP_STRINGIFY () {" . opnumber("stringify") . "}" }

sub pp_null {
    my $self = shift;
    my($op, $cx) = @_;
    if (class($op) eq "OP") {
	# old value is lost
	return $self->{'ex_const'} if $op->targ == OP_CONST;
    } elsif ($op->first->name eq "pushmark") {
	return $self->pp_list($op, $cx);
    } elsif ($op->first->name eq "enter") {
	return $self->pp_leave($op, $cx);
    } elsif ($op->targ == OP_STRINGIFY) {
	return $self->dquote($op, $cx);
    } elsif (!null($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 eq "trans" and
	     $op->first->sibling->flags & OPf_STACKED) {
	return $self->maybe_parens($self->deparse($op->first, 20) . " =~ "
				   . $self->deparse($op->first->sibling, 20),
				   $cx, 20);
    } 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) = @_;
    return $self->maybe_my($op, $cx, $self->padname($op->targ));
}

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

my @threadsv_names;

BEGIN {
    @threadsv_names = ("_", "1", "2", "3", "4", "5", "6", "7", "8", "9",
		       "&", "`", "'", "+", "/", ".", ",", "\\", '"', ";",
		       "^", "-", "%", "=", "|", "~", ":", "^A", "^E",
		       "!", "@");
}

sub pp_threadsv {
    my $self = shift;
    my($op, $cx) = @_;
    return $self->maybe_local($op, $cx, "\$" .  $threadsv_names[$op->targ]);
}    

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, "\$" . $self->gv_name($gv));
}

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

sub pp_aelemfast {
    my $self = shift;
    my($op, $cx) = @_;
    my $gv = $self->gv_or_padgv($op);
    return "\$" . $self->gv_name($gv) . "[" . $op->private . "]";
}

sub rv2x {
    my $self = shift;
    my($op, $cx, $type) = @_;
    my $kid = $op->first;
    my $str = $self->deparse($kid, 0);
    return $type . (is_scalar($kid) ? $str : "{$str}");
}

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 { $_[0]->rv2x($_[1]->first->first->sibling, $_[2], "&") }

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 "(" . join(", ", map(const($_), $av->ARRAY)) . ")";
    } else {
	return $self->maybe_local($op, $cx, $self->rv2x($op, $cx, "\@"));
    }
 }

sub is_subscriptable {
    my $op = shift;
    if ($op->name =~ /^[ahg]elem/) {
	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 $kid->name eq "gv";
	return 0 if is_scalar($kid);
	return is_subscriptable($kid);	
    } else {
	return 0;
    }
}

sub elem {
    my $self = shift;
    my ($op, $cx, $left, $right, $padname) = @_;
    my($array, $idx) = ($op->first, $op->first->sibling);
    unless ($array->name eq $padname) { # Maybe this has been fixed	
	$array = $array->first; # skip rv2av (or ex-rv2av in _53+)
    }
    if ($array->name eq $padname) {
	$array = $self->padany($array);
    } elsif (is_scope($array)) { # ${expr}[0]
	$array = "{" . $self->deparse($array, 0) . "}";
    } elsif (is_scalar $array) { # $x[0], $$x[0], ...
	$array = $self->deparse($array, 24);
    } else {
	# $x[20][3]{hi} or expr->[20]
	my $arrow = is_subscriptable($array) ? "" : "->";
	return $self->deparse($array, 24) . $arrow .
	    $left . $self->deparse($idx, 1) . $right;
    }
    $idx = $self->deparse($idx, 1);
    return "\$" . $array . $left . $idx . $right;
}

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 $array->name eq "null";
    if (is_scope($array)) {
	$array = "{" . $self->deparse($array, 0) . "}";
    } elsif ($array->name eq $padname) {
	$array = $self->padany($array);
    } else {
	$array = $self->deparse($array, 24);
    }
    $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 = $self->deparse($kid, 1);
    }
    return "\@" . $array . $left . $list . $right;
}

sub pp_aslice { maybe_local(@_, slice(@_, "[", "]", "rv2av", "padav")) }
sub pp_hslice { maybe_local(@_, 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, $self->deparse($kid, 6);
	}
    } else {
	$obj = $kid;
	$kid = $kid->sibling;
	for (; not null $kid->sibling; $kid = $kid->sibling) {
	    push @exprs, $self->deparse($kid, 6);
	}
	$meth = $kid;
    }
    $obj = $self->deparse($obj, 24);
    if ($meth->name eq "method_named") {
	$meth = $self->const_sv($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
	} else {
	    $meth = $self->deparse($meth, 1);
	}
    }
    my $args = join(", ", @exprs);	
    $kid = $obj . "->" . $meth;
    if ($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 $self = shift;
    my($proto, @args) = @_;
    my($arg, $real);
    my $doneok = 0;
    my @reals;
    # An unbackslashed @ or % gobbles up the rest of the args
    $proto =~ s/([^\\]|^)([@%])(.*)$/$1$2/;
    while ($proto) {
	$proto =~ 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 "\$") {
		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 "\\") {
		$chr = substr($chr, 1);
		if ($arg->name =~ /^s?refgen$/ and
		    !null($real = $arg->first) and
		    ($chr eq "\$" && is_scalar($real->first)
		     or ($chr eq "\@"
			 && $real->first->sibling->name
			 =~ /^(rv2|pad)av$/)
		     or ($chr eq "%"
			 && $real->first->sibling->name
			 =~ /^(rv2|pad)hv$/)
		     #or ($chr eq "&" # This doesn't work
		     #   && $real->first->name eq "rv2cv")
		     or ($chr eq "*"
			 && $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 pp_entersub {
    my $self = shift;
    my($op, $cx) = @_;
    return $self->method($op, $cx) unless null $op->first->sibling;
    my $prefix = "";
    my $amper = "";
    my($kid, @exprs);
    if ($op->flags & OPf_SPECIAL) {
	$prefix = "do ";
    } elsif ($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 $proto = undef;
    if (is_scope($kid)) {
	$amper = "&";
	$kid = "{" . $self->deparse($kid, 0) . "}";
    } elsif ($kid->first->name eq "gv") {
	my $gv = $self->gv_or_padgv($kid->first);
	if (class($gv->CV) ne "SPECIAL") {
	    $proto = $gv->CV->PV if $gv->CV->FLAGS & SVf_POK;
	}
	$simple = 1; # only calls of named functions can be prototyped
	$kid = $self->deparse($kid, 24);
    } elsif (is_scalar $kid->first) {
	$amper = "&";
	$kid = $self->deparse($kid, 24);
    } else {
	$prefix = "";
	my $arrow = is_subscriptable($kid->first) ? "" : "->";
	$kid = $self->deparse($kid, 24) . $arrow;
    }
    my $args;
    if (defined $proto and not $amper) {
	($amper, $args) = $self->check_proto($proto, @exprs);
	if ($amper eq "&") {
	    $args = join(", ", map($self->deparse($_, 6), @exprs));
	}
    } else {
	$args = join(", ", map($self->deparse($_, 6), @exprs));
    }
    if ($prefix or $amper) {
	if ($op->flags & OPf_STACKED) {
	    return $prefix . $amper . $kid . "(" . $args . ")";
	} else {
	    return $prefix . $amper. $kid;
	}
    } else {
	if (defined $proto and $proto eq "") {
	    return $kid;
	} elsif (defined $proto and $proto eq "\$") {
	    return $self->maybe_parens_func($kid, $args, $cx, 16);
	} elsif (defined($proto) && $proto or $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/(^|[^\\])([\$\@]|\\[uUlLQE])/$1\\$2/g;
    return $str;
}

# the same, but treat $|, $), and $ at the end of the string differently
sub re_uninterp {
    my($str) = @_;
    $str =~ s/(^|[^\\])(\@|\\[uUlLQE])/$1\\$2/g;
    $str =~ s/(^|[^\\])(\$[^)|])/$1\\$2/g;
    return $str;
}

# character escapes, but not delimiters that might need to be escaped
sub escape_str { # ASCII
    my($str) = @_;
    $str =~ s/\a/\\a/g;
#    $str =~ s/\cH/\\b/g; # \b means someting different in a regex 
    $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' . chr(ord('@') + ord($1))/ge;
    $str =~ s/([\0\033-\037\177-\377])/'\\' . sprintf("%03o", ord($1))/ge;
    return $str;
}

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

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

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

sub const {
    my $sv = shift;
    if (class($sv) eq "SPECIAL") {
	return ('undef', '1', '0')[$$sv-1]; # sv_undef, sv_yes, sv_no
    } elsif ($sv->FLAGS & SVf_IOK) {
	return $sv->int_value;
    } elsif ($sv->FLAGS & SVf_NOK) {
	return $sv->NV;
    } elsif ($sv->FLAGS & SVf_ROK) {
	return "\\(" . const($sv->RV) . ")"; # constant folded
    } else {
	my $str = $sv->PV;
	if ($str =~ /[^ -~]/) { # ASCII for non-printing
	    return single_delim("qq", '"', uninterp escape_str unback $str);
	} else {
	    return single_delim("q", "'", unback $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 pp_const {
    my $self = shift;
    my($op, $cx) = @_;
#    if ($op->private & OPpCONST_BARE) { # trouble with `=>' autoquoting 
#	return $self->const_sv($op)->PV;
#    }
    my $sv = $self->const_sv($op);
#    return const($sv);
    my $c = const $sv; 
    return $c =~ /^-\d/ ? $self->maybe_parens($c, $cx, 21) : $c;
}

sub dq {
    my $self = shift;
    my $op = shift;
    my $type = $op->name;
    if ($type eq "const") {
	return uninterp(escape_str(unback($self->const_sv($op)->PV)));
    } elsif ($type eq "concat") {
	my $first = $self->dq($op->first);
	my $last  = $self->dq($op->last);
	# Disambiguate "${foo}bar", "${foo}{bar}", "${foo}[1]"
        if ($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 "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
    return single_delim("qx", '`', $self->dq($op->first->sibling));
}

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]))});
}

# OP_STRINGIFY is a listop, but it only ever has one arg
sub pp_stringify { maybe_targmy(@_, \&dquote) }

# 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/";	
    }
}

sub pchr { # ASCII
    my($n) = @_;
    if ($n == ord '\\') {
	return '\\\\';
    } elsif ($n >= ord(' ') and $n <= ord('~')) {
	return chr($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' . chr(ord("@") + $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++)
	      {}
#mdupont""
	    $str .= "-";
	    $str .= pchr($chars[$c]);
	}
    }
    return $str;
}

# XXX This has trouble with hyphens in the replacement (tr/bac/-AC/),
# and backslashes.

sub tr_decode_byte {
    my($table, $flags) = @_;
    my(@table) = unpack("s256", $table);
    my($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 < 256; $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 "\\-";
    } 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, $cx) = @_;
    my($from, $to);
    if (class($op) eq "PVOP") {
	($from, $to) = tr_decode_byte($op->pv, $op->private);
    } else { # class($op) eq "SVOP"
	($from, $to) = tr_decode_utf8($op->sv->RV, $op->private);
    }
    my $flags = "";
    $flags .= "c" if $op->private & OPpTRANS_COMPLEMENT;
    $flags .= "d" if $op->private & OPpTRANS_DELETE;
    $to = "" if $from eq $to and $flags eq "";
    $flags .= "s" if $op->private & OPpTRANS_SQUASH;
    return "tr" . double_delim($from, $to) . $flags;
}

# Like dq(), but different
sub re_dq {
    my $self = shift;
    my $op = shift;
    my $type = $op->name;
    if ($type eq "const") {
	return re_uninterp($self->const_sv($op)->PV);
    } elsif ($type eq "concat") {
	my $first = $self->re_dq($op->first);
	my $last  = $self->re_dq($op->last);
	# Disambiguate "${foo}bar", "${foo}{bar}", "${foo}[1]"
	if ($last =~ /^[{\[\w]/) {
	    $first =~ s/([%\$@])([A-Za-z_]\w*)$/${1}{$2}/;
	}
	return $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 "join") {
	return $self->deparse($op->last, 26); # was join($", @ary)
    } else {
	return $self->deparse($op, 26);
    }
}

sub pp_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";
    return $self->re_dq($kid);
}

# 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'); 

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;
    }
    if (null $kid) {
	$re = re_uninterp(escape_str($op->precomp));
    } else {
	$re = $self->deparse($kid, 1);
    }
    my $flags = "";
    $flags .= "c" if $op->pmflags & PMf_CONTINUE;
    $flags .= "g" if $op->pmflags & PMf_GLOBAL;
    $flags .= "i" if $op->pmflags & PMf_FOLD;
    $flags .= "m" if $op->pmflags & PMf_MULTILINE;
    $flags .= "o" if $op->pmflags & PMf_KEEP;
    $flags .= "s" if $op->pmflags & PMf_SINGLELINE;
    $flags .= "x" if $op->pmflags & PMf_EXTENDED;
    $flags = $matchwords{$flags} if $matchwords{$flags};
    if ($op->pmflags & PMf_ONCE) { # only one kind of delimiter works here
	$re =~ s/\?/\\?/g;
	$re = "?$re?";
    } else {
	$re = single_delim($name, $delim, $re);
    }
    $re = $re . $flags;
    if ($binop) {
	return $self->maybe_parens("$var =~ $re", $cx, 20);
    } else {
	return $re;
    }
}

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

sub pp_split {
    my $self = shift;
    my($op, $cx) = @_;
    my($kid, @exprs, $ary, $expr);
    $kid = $op->first;
    if ($ {$kid->pmreplroot}) {
	$ary = '@' . $self->gv_name($kid->pmreplroot);
    }
    for (; !null($kid); $kid = $kid->sibling) {
	push @exprs, $self->deparse($kid, 6);
    }
    $expr = "split(" . join(", ", @exprs) . ")";
    if ($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');

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;
    }
    my $flags = "";    
    if (null($op->pmreplroot)) {
	$repl = $self->dq($kid);
	$kid = $kid->sibling;
    } else {
	$repl = $op->pmreplroot->first; # skip substcont
	while ($repl->name eq "entereval") {
	    $repl = $repl->first;
	    $flags .= "e";
	}
	if ($op->pmflags & PMf_EVAL) {
	    $repl = $self->deparse($repl, 0);
	} else {
	    $repl = $self->dq($repl);	
	}
    }
    if (null $kid) {
	$re = re_uninterp(escape_str($op->precomp));
    } else {
	$re = $self->deparse($kid, 1);
    }
    $flags .= "e" if $op->pmflags & PMf_EVAL;
    $flags .= "g" if $op->pmflags & PMf_GLOBAL;
    $flags .= "i" if $op->pmflags & PMf_FOLD;
    $flags .= "m" if $op->pmflags & PMf_MULTILINE;
    $flags .= "o" if $op->pmflags & PMf_KEEP;
    $flags .= "s" if $op->pmflags & PMf_SINGLELINE;
    $flags .= "x" if $op->pmflags & PMf_EXTENDED;
    $flags = $substwords{$flags} if $substwords{$flags};
    if ($binop) {
	return $self->maybe_parens("$var =~ s"
				   . double_delim($re, $repl) . $flags,
				   $cx, 20);
    } else {
	return "s". double_delim($re, $repl) . $flags;	
    }
}

sub compile_main
{
    my  @args = @_;

	my $self = B::Introspector->new(@args);
	
	$self->stash_subs("main");
	$self->{'curcv'} = main_cv;
	
	$self->walk_sub(main_cv, main_start);
	
	print $self->print_protos;
	
	@{$self->{'subs_todo'}} =
	  sort {$a->[0] <=> $b->[0]} @{$self->{'subs_todo'}};
	
	print $self->indent($self->deparse(main_root, 0)), "\n"
	  unless null main_root;
	
	my @text;

	while (scalar(@{$self->{'subs_todo'}})) {
	    push @text, $self->next_todo;
	}

	print $self->indent(join("", @text)), "\n" if @text;

}
### Modified by mdupont
sub compile {
    my(@args) = @_;
    return sub { 
	#print Dumper(\@args);
	compile_main @args;
    }
}

1;