deparse.pm

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	}
	$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 { 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) }