package B::Deparse;
use Carp 'cluck', 'croak';
-use B qw(class main_root main_start main_cv svref_2object opnumber
+use B qw(class main_root main_start main_cv svref_2object opnumber cstring
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
+ OPpCONST_ARYBASE OPpEXISTS_SUB
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_KEEP PMf_GLOBAL PMf_CONTINUE PMf_EVAL PMf_ONCE PMf_SKIPWHITE
PMf_MULTILINE PMf_SINGLELINE PMf_FOLD PMf_EXTENDED);
-$VERSION = 0.591;
+$VERSION = 0.60;
use strict;
+use warnings ();
# Changes between 0.50 and 0.51:
# - fixed nulled leave with live enter in sort { }
# - 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 in high bit chars in string as utf8 \x{...} (when?)
-# - copy comments (look at real text with $^P?)
+# - copy comments (look at real text with $^P?)
# - avoid semis in one-statement blocks
# - associativity of &&=, ||=, ?:
# - ',' => '=>' (auto-unquote?)
# - 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'?
-# - while{} with one-statement continue => for(; XXX; XXX) {}?
-# - -uPackage:: descend recursively?
# - here-docs?
# - <DATA>?
# curcv:
# CV for current sub (or main program) being deparsed
#
+# curcvlex:
+# Cached hash of lexical variables for curcv: keys are names,
+# each value is an array of pairs, indicating the cop_seq of scopes
+# in which a var of that name is valid.
+#
+# curcop:
+# COP for statement 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
+# array of [cop_seq, CV, is_format?] for subs and formats we still
# want to deparse
#
# protos_todo:
# keys are addresses of GVs for subs and formats we've already
# deparsed (or at least put into subs_todo)
#
+# subs_declared
+# keys are names of subs for which we've printed declarations.
+# That means we can omit parentheses from the arguments.
+#
# parens: -p
# linenums: -l
# unquote: -q
sub todo {
my $self = shift;
- my($gv, $cv, $is_form) = @_;
+ my($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, $is_form];
+ push @{$self->{'subs_todo'}}, [$seq, $cv, $is_form];
}
sub next_todo {
my $self = shift;
my $ent = shift @{$self->{'subs_todo'}};
- my $name = $self->gv_name($ent->[1]);
+ my $cv = $ent->[1];
+ my $gv = $cv->GV;
+ my $name = $self->gv_name($gv);
if ($ent->[2]) {
return "format $name =\n"
. $self->deparse_format($ent->[1]->FORM). "\n";
} else {
- return "sub $name " . $self->deparse_sub($ent->[1]->CV);
+ $self->{'subs_declared'}{$name} = 1;
+ if ($name eq "BEGIN") {
+ my $use_dec = $self->begin_is_use($cv);
+ if (defined ($use_dec)) {
+ return () if 0 == length($use_dec);
+ return $use_dec;
+ }
+ }
+ return "sub $name " . $self->deparse_sub($cv);
+ }
+}
+
+# Return a "use" declaration for this BEGIN block, if appropriate
+sub begin_is_use {
+ my ($self, $cv) = @_;
+ my $root = $cv->ROOT;
+#require B::Debug;
+#B::walkoptree($cv->ROOT, "debug");
+ my $lineseq = $root->first;
+ return if $lineseq->name ne "lineseq";
+
+ my $req_op = $lineseq->first->sibling;
+ return if $req_op->name ne "require";
+
+ my $module;
+ if ($req_op->first->private & OPpCONST_BARE) {
+ # Actually it should always be a bareword
+ $module = $self->const_sv($req_op->first)->PV;
+ $module =~ s[/][::]g;
+ $module =~ s/.pm$//;
+ }
+ else {
+ $module = const($self->const_sv($req_op->first));
+ }
+
+ my $version;
+ my $version_op = $req_op->sibling;
+ return if class($version_op) eq "NULL";
+ if ($version_op->name eq "lineseq") {
+ # We have a version parameter; skip nextstate & pushmark
+ my $constop = $version_op->first->next->next;
+
+ return unless $self->const_sv($constop)->PV eq $module;
+ $constop = $constop->sibling;
+
+ $version = $self->const_sv($constop)->int_value;
+ $constop = $constop->sibling;
+ return if $constop->name ne "method_named";
+ return if $self->const_sv($constop)->PV ne "VERSION";
+ }
+
+ $lineseq = $version_op->sibling;
+ return if $lineseq->name ne "lineseq";
+ my $entersub = $lineseq->first->sibling;
+ if ($entersub->name eq "stub") {
+ return "use $module $version ();\n" if defined $version;
+ return "use $module ();\n";
+ }
+ return if $entersub->name ne "entersub";
+
+ # See if there are import arguments
+ my $args = '';
+
+ my $constop = $entersub->first->sibling; # Skip over pushmark
+ return unless $self->const_sv($constop)->PV eq $module;
+
+ # Pull out the arguments
+ for ($constop=$constop->sibling; $constop->name eq "const";
+ $constop = $constop->sibling) {
+ $args .= ", " if length($args);
+ $args .= $self->deparse($constop, 6);
+ }
+
+ my $use = 'use';
+ my $method_named = $constop;
+ return if $method_named->name ne "method_named";
+ my $method_name = $self->const_sv($method_named)->PV;
+
+ if ($method_name eq "unimport") {
+ $use = 'no';
+ }
+
+ # Certain pragmas are dealt with using hint bits,
+ # so we ignore them here
+ if ($module eq 'strict' || $module eq 'integer'
+ || $module eq 'bytes' || $module eq 'warnings') {
+ return "";
+ }
+
+ if (defined $version && length $args) {
+ return "$use $module $version ($args);\n";
+ } elsif (defined $version) {
+ return "$use $module $version;\n";
+ } elsif (length $args) {
+ return "$use $module ($args);\n";
+ } else {
+ return "$use $module;\n";
}
}
if ($op->next->name eq "entersub") {
return if $self->{'subs_done'}{$$gv}++;
return if class($gv->CV) eq "SPECIAL";
- $self->todo($gv, $gv->CV, 0);
+ $self->todo($gv->CV, 0);
$self->walk_sub($gv->CV);
} elsif ($op->next->name eq "enterwrite"
or ($op->next->name eq "rv2gv"
and $op->next->next->name eq "enterwrite")) {
return if $self->{'forms_done'}{$$gv}++;
return if class($gv->FORM) eq "SPECIAL";
- $self->todo($gv, $gv->FORM, 1);
+ $self->todo($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 = $pack . "::";
+ my ($self, $pack) = @_;
+ my (@ret, $stash);
+ if (!defined $pack) {
+ $pack = '';
+ $stash = \%::;
}
- my($key, $val);
- while (($key, $val) = each %stash) {
+ else {
+ $pack =~ s/(::)?$/::/;
+ no strict 'refs';
+ $stash = \%$pack;
+ }
+ my %stash = svref_2object($stash)->ARRAY;
+ while (my ($key, $val) = each %stash) {
+ next if $key eq 'main::'; # avoid infinite recursion
+ next if $key eq 'B::'; # don't automatically scan B
my $class = class($val);
if ($class eq "PV") {
# Just a prototype
# Just a name
push @{$self->{'protos_todo'}}, [$pack . $key, undef];
} elsif ($class eq "GV") {
- if (class($val->CV) ne "SPECIAL") {
+ if (class(my $cv = $val->CV) ne "SPECIAL") {
+ next unless $cv->FILE eq $0 || $self->{'files'}{$cv->FILE};
next if $self->{'subs_done'}{$$val}++;
- $self->todo($val, $val->CV, 0);
- $self->walk_sub($val->CV);
+ next if ${$cv->GV} != $$val;
+ $self->todo($cv, 0);
+ $self->walk_sub($cv);
}
if (class($val->FORM) ne "SPECIAL") {
next if $self->{'forms_done'}{$$val}++;
- $self->todo($val, $val->FORM, 1);
+ $self->todo($val->FORM, 1);
$self->walk_sub($val->FORM);
}
+ if (class($val->HV) ne "SPECIAL" && $key =~ /::$/) {
+ $self->stash_subs($pack . $key);
+ }
}
}
}
my $class = shift;
my $self = bless {}, $class;
$self->{'subs_todo'} = [];
+ $self->{'files'} = {};
$self->{'curstash'} = "main";
+ $self->{'curcop'} = undef;
$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'} = "'???'";
+
+ $self->{'ambient_arybase'} = 0;
+ $self->{'ambient_warnings'} = "\0"x12;
+ $self->{'ambient_hints'} = 0;
+ $self->init();
+
while (my $arg = shift @_) {
- if (substr($arg, 0, 2) eq "-u") {
- $self->stash_subs(substr($arg, 2));
+ if ($arg =~ /^-f(.*)/) {
+ $self->{'files'}{$1} = 1;
} elsif ($arg eq "-p") {
$self->{'parens'} = 1;
} elsif ($arg eq "-l") {
$self->{'unquote'} = 1;
} elsif (substr($arg, 0, 2) eq "-s") {
$self->style_opts(substr $arg, 2);
+ } elsif ($arg =~ /^-x(\d)$/) {
+ $self->{'expand'} = $1;
}
}
return $self;
}
+sub WARN_MASK () {
+ # Mask out the bits that C<use vars> uses
+ $warnings::Bits{all} | $warnings::DeadBits{all};
+}
+
+# Initialise the contextual information, either from
+# defaults provided with the ambient_pragmas method,
+# or from perl's own defaults otherwise.
+sub init {
+ my $self = shift;
+
+ $self->{'arybase'} = $self->{'ambient_arybase'};
+ $self->{'warnings'} = $self->{'ambient_warnings'} & WARN_MASK;
+ $self->{'hints'} = $self->{'ambient_hints'} & 0xFF;
+
+ # also a convenient place to clear out subs_declared
+ delete $self->{'subs_declared'};
+}
+
sub compile {
my(@args) = @_;
return sub {
my $self = B::Deparse->new(@args);
- $self->stash_subs("main");
+ my @BEGINs = B::begin_av->isa("B::AV") ? B::begin_av->ARRAY : ();
+ my @INITs = B::init_av->isa("B::AV") ? B::init_av->ARRAY : ();
+ my @ENDs = B::end_av->isa("B::AV") ? B::end_av->ARRAY : ();
+ for my $block (@BEGINs, @INITs, @ENDs) {
+ if ($block->FILE eq $0 || $self->{'files'}{$block->FILE}) {
+ $self->todo($block, 0);
+ $self->walk_sub($block);
+ }
+ }
+ $self->stash_subs();
$self->{'curcv'} = main_cv;
+ $self->{'curcvlex'} = undef;
$self->walk_sub(main_cv, main_start);
print $self->print_protos;
@{$self->{'subs_todo'}} =
my $self = shift;
my $sub = shift;
croak "Usage: ->coderef2text(CODEREF)" unless ref($sub) eq "CODE";
+
+ $self->init();
return $self->indent($self->deparse_sub(svref_2object($sub)));
}
+sub ambient_pragmas {
+ my $self = shift;
+ my ($arybase, $hint_bits, $warning_bits) = (0, 0, "\0"x12);
+
+ while (@_ > 1) {
+ my $name = shift();
+ my $val = shift();
+
+ if ($name eq 'strict') {
+ require strict;
+
+ if ($val eq 'none') {
+ $hint_bits &= ~strict::bits(qw/refs subs vars/);
+ next();
+ }
+
+ my @names;
+ if ($val eq "all") {
+ @names = qw/refs subs vars/;
+ }
+ elsif (ref $val) {
+ @names = @$val;
+ }
+ else {
+ @names = split' ', $val;
+ }
+ $hint_bits |= strict::bits(@names);
+ }
+
+ elsif ($name eq '$[') {
+ $arybase = $val;
+ }
+
+ elsif ($name eq 'integer'
+ || $name eq 'bytes'
+ || $name eq 'utf8') {
+ require "$name.pm";
+ if ($val) {
+ $hint_bits |= ${$::{"${name}::"}{"hint_bits"}};
+ }
+ else {
+ $hint_bits &= ~${$::{"${name}::"}{"hint_bits"}};
+ }
+ }
+
+ elsif ($name eq 're') {
+ require re;
+ if ($val eq 'none') {
+ $hint_bits &= ~re::bits(qw/taint eval asciirange/);
+ next();
+ }
+
+ my @names;
+ if ($val eq 'all') {
+ @names = qw/taint eval asciirange/;
+ }
+ elsif (ref $val) {
+ @names = @$val;
+ }
+ else {
+ @names = split' ',$val;
+ }
+ $hint_bits |= re::bits(@names);
+ }
+
+ elsif ($name eq 'warnings') {
+ if ($val eq 'none') {
+ $warning_bits = "\0"x12;
+ next();
+ }
+
+ my @names;
+ if (ref $val) {
+ @names = @$val;
+ }
+ else {
+ @names = split/\s+/, $val;
+ }
+
+ $warning_bits |= warnings::bits(@names);
+ }
+
+ elsif ($name eq 'warning_bits') {
+ $warning_bits = $val;
+ }
+
+ elsif ($name eq 'hint_bits') {
+ $hint_bits = $val;
+ }
+
+ else {
+ croak "Unknown pragma type: $name";
+ }
+ }
+ if (@_) {
+ croak "The ambient_pragmas method expects an even number of args";
+ }
+
+ $self->{'ambient_arybase'} = $arybase;
+ $self->{'ambient_warnings'} = $warning_bits;
+ $self->{'ambient_hints'} = $hint_bits;
+}
+
sub deparse {
my $self = shift;
my($op, $cx) = @_;
-# cluck if class($op) eq "NULL";
-# return $self->$ {\("pp_" . $op->name)}($op, $cx);
+
+ Carp::confess("Null op in deparse") if !defined($op)
+ || class($op) eq "NULL";
my $meth = "pp_" . $op->name;
return $self->$meth($op, $cx);
}
my $self = shift;
my $cv = shift;
my $proto = "";
+Carp::confess("SPECIAL in deparse_sub") if $cv->isa("B::SPECIAL");
+ local $self->{'curcop'} = $self->{'curcop'};
if ($cv->FLAGS & SVf_POK) {
$proto = "(". $cv->PV . ") ";
}
}
local($self->{'curcv'}) = $cv;
- local($self->{'curstash'}) = $self->{'curstash'};
+ local($self->{'curcvlex'});
+ local(@$self{qw'curstash warnings hints'})
+ = @$self{qw'curstash warnings hints'};
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";
+ }
+ my $sv = $cv->const_sv;
+ if ($$sv) {
+ # uh-oh. inlinable sub... format it differently
+ return $proto . "{ " . const($sv) . " }\n";
+ } else { # XSUB? (or just a declaration)
+ return "$proto;\n";
}
}
my $form = shift;
my @text;
local($self->{'curcv'}) = $form;
- local($self->{'curstash'}) = $self->{'curstash'};
+ local($self->{'curcvlex'});
+ local(@$self{qw'curstash warnings hints'})
+ = @$self{'curstash warnings hints'};
my $op = $form->ROOT;
my $kid;
$op = $op->first->first; # skip leavewrite, lineseq
my $self = shift;
my($op, $cx, $text) = @_;
if ($op->private & OPpLVAL_INTRO and not $self->{'avoid_local'}{$$op}) {
- return $self->maybe_parens_func("local", $text, $cx, 16);
+ if (want_scalar($op)) {
+ return "local $text";
+ } else {
+ return $self->maybe_parens_func("local", $text, $cx, 16);
+ }
} else {
return $text;
}
my $self = shift;
my($op, $cx, $text) = @_;
if ($op->private & OPpLVAL_INTRO and not $self->{'avoid_local'}{$$op}) {
- return $self->maybe_parens_func("my", $text, $cx, 16);
+ if (want_scalar($op)) {
+ return "my $text";
+ } else {
+ return $self->maybe_parens_func("my", $text, $cx, 16);
+ }
} else {
return $text;
}
return "XXX";
}
-# leave and scope/lineseq should probably share code
-sub pp_leave {
+sub lineseq {
my $self = shift;
- my($op, $cx) = @_;
- my ($kid, $expr);
- my @exprs;
- local($self->{'curstash'}) = $self->{'curstash'};
- $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";
- }
- for (; !null($kid); $kid = $kid->sibling) {
+ my(@ops) = @_;
+ my($expr, @exprs);
+ for (my $i = 0; $i < @ops; $i++) {
$expr = "";
- if (is_state $kid) {
- $expr = $self->deparse($kid, 0);
- $kid = $kid->sibling;
- last if null $kid;
+ 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($kid, 0);
+ $expr .= $self->deparse($ops[$i], 0);
push @exprs, $expr if length $expr;
}
- if ($cx > 0) { # inside an expression
- return "do { " . join(";\n", @exprs) . " }";
- } else {
- return join(";\n", @exprs) . ";";
- }
+ for(@exprs[0..@exprs-1]) { s/;\n\z// }
+ return join(";\n", @exprs);
}
-sub pp_scope {
- my $self = shift;
- my($op, $cx) = @_;
- my ($kid, $expr);
- my @exprs;
- for ($kid = $op->first; !null($kid); $kid = $kid->sibling) {
- $expr = "";
- if (is_state $kid) {
- $expr = $self->deparse($kid, 0);
- $kid = $kid->sibling;
- last if null $kid;
+sub scopeop {
+ my($real_block, $self, $op, $cx) = @_;
+ my $kid;
+ my @kids;
+
+ local(@$self{qw'curstash warnings hints'})
+ = @$self{qw'curstash warnings hints'} 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";
}
- $expr .= $self->deparse($kid, 0);
- push @exprs, $expr if length $expr;
+ } 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 { " . join(";\n", @exprs) . " }";
+ return "do { " . $self->lineseq(@kids) . " }";
} else {
- return join(";\n", @exprs) . ";";
+ my $lineseq = $self->lineseq(@kids);
+ return (length ($lineseq) ? "$lineseq;" : "");
}
}
-sub pp_lineseq { pp_scope(@_) }
+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.
sub gv_name {
my $self = shift;
my $gv = shift;
+Carp::confess() if $gv->isa("B::CV");
my $stash = $gv->STASH->NAME;
- my $name = $gv->NAME;
+ my $name = $gv->SAFENAME;
if ($stash eq $self->{'curstash'} or $globalnames{$name}
or $name =~ /^[^A-Za-z_]/)
{
} else {
$stash = $stash . "::";
}
- if ($name =~ /^([\cA-\cZ])$/) {
- $name = "^" . chr(64 + ord($1));
+ if ($name =~ /^\^../) {
+ $name = "{$name}"; # ${^WARNING_BITS} etc
}
return $stash . $name;
}
-# Notice how subs and formats are inserted between statements here
-sub pp_nextstate {
+# Return the name to use for a stash variable.
+# If a lexical with the same name is in scope, it may need to be
+# fully-qualified.
+sub stash_variable {
+ my ($self, $prefix, $name) = @_;
+
+ return "$prefix$name" if $name =~ /::/;
+
+ unless ($prefix eq '$' || $prefix eq '@' ||
+ $prefix eq '%' || $prefix eq '$#') {
+ return "$prefix$name";
+ }
+
+ my $v = ($prefix eq '$#' ? '@' : $prefix) . $name;
+ return $prefix .$self->{'curstash'}.'::'. $name if $self->lex_in_scope($v);
+ return "$prefix$name";
+}
+
+sub lex_in_scope {
+ my ($self, $name) = @_;
+ $self->populate_curcvlex() if !defined $self->{'curcvlex'};
+
+ my $seq = $self->{'curcop'}->cop_seq;
+ return 0 if !exists $self->{'curcvlex'}{$name};
+ for my $a (@{$self->{'curcvlex'}{$name}}) {
+ my ($st, $en) = @$a;
+ return 1 if $seq > $st && $seq <= $en;
+ }
+ return 0;
+}
+
+sub populate_curcvlex {
my $self = shift;
- my($op, $cx) = @_;
- my @text;
- @text = $op->label . ": " if $op->label;
+ for (my $cv = $self->{'curcv'}; $$cv; $cv = $cv->OUTSIDE) {
+ my @padlist = $cv->PADLIST->ARRAY;
+ my @ns = $padlist[0]->ARRAY;
+
+ for (my $i=0; $i<@ns; ++$i) {
+ next if class($ns[$i]) eq "SPECIAL";
+ if (class($ns[$i]) eq "PV") {
+ # Probably that pesky lexical @_
+ next;
+ }
+ my $name = $ns[$i]->PVX;
+ my $seq_st = $ns[$i]->NVX;
+ my $seq_en = int($ns[$i]->IVX);
+
+ push @{$self->{'curcvlex'}{$name}}, [$seq_st, $seq_en];
+ }
+ }
+}
+
+# Recurses down the tree, looking for a COP
+sub find_cop {
+ my ($self, $op) = @_;
+ if ($op->flags & OPf_KIDS) {
+ for (my $o=$op->first; $$o; $o=$o->sibling) {
+ return $o if is_state($o);
+ my $r = $self->find_cop($o);
+ return $r if defined $r;
+ }
+ }
+ return undef;
+}
+
+# Returns a list of subs which should be inserted before the COP
+sub cop_subs {
+ my ($self, $op, $out_seq) = @_;
my $seq = $op->cop_seq;
+ # If we have nephews, then our sequence number indicates
+ # the cop_seq of the end of some sort of scope.
+ if (class($op->sibling) ne "NULL" && $op->sibling->flags & OPf_KIDS
+ and my $ncop = $self->find_cop($op->sibling)) {
+ $seq = $ncop->cop_seq;
+ }
+ $seq = $out_seq if defined($out_seq) && $out_seq < $seq;
+ return $self->seq_subs($seq);
+}
+
+sub seq_subs {
+ my ($self, $seq) = @_;
+ my @text;
+#push @text, "# ($seq)\n";
+
while (scalar(@{$self->{'subs_todo'}})
and $seq > $self->{'subs_todo'}[0][0]) {
push @text, $self->next_todo;
}
+ return @text;
+}
+
+# Notice how subs and formats are inserted between statements here;
+# also $[ assignments and pragmas.
+sub pp_nextstate {
+ my $self = shift;
+ my($op, $cx) = @_;
+ $self->{'curcop'} = $op;
+ my @text;
+ @text = $op->label . ": " if $op->label;
+#push @text, "# ", $op->cop_seq, "\n";
+ push @text, $self->cop_subs($op);
my $stash = $op->stashpv;
if ($stash ne $self->{'curstash'}) {
push @text, "package $stash;\n";
push @text, "\f#line " . $op->line .
' "' . $op->file, qq'"\n';
}
+
+ if ($self->{'arybase'} != $op->arybase) {
+ push @text, '$[ = '. $op->arybase .";\n";
+ $self->{'arybase'} = $op->arybase;
+ }
+
+ my $warnings = $op->warnings;
+ my $warning_bits;
+ if ($warnings->isa("B::SPECIAL") && $$warnings == 4) {
+ $warning_bits = $warnings::Bits{"all"};
+ }
+ elsif ($warnings->isa("B::SPECIAL")) {
+ $warning_bits = "\0"x12;
+ }
+ else {
+ $warning_bits = $warnings->PV & WARN_MASK;
+ }
+
+ if ($self->{'warnings'} ne $warning_bits) {
+ push @text, declare_warnings($self->{'warnings'}, $warning_bits);
+ $self->{'warnings'} = $warning_bits;
+ }
+
+ if ($self->{'hints'} != $op->private) {
+ push @text, declare_hints($self->{'hints'}, $op->private);
+ $self->{'hints'} = $op->private;
+ }
+
return join("", @text);
}
+sub declare_warnings {
+ my ($from, $to) = @_;
+ if ($to eq warnings::bits("all")) {
+ return "use warnings;\n";
+ }
+ elsif ($to eq "\0"x12) {
+ return "no warnings;\n";
+ }
+ return "BEGIN {\${^WARNING_BITS} = ".cstring($to)."}\n";
+}
+
+sub declare_hints {
+ my ($from, $to) = @_;
+ my $bits = $to;
+ return sprintf "BEGIN {\$^H &= ~0xFF; \$^H |= %x}\n", $bits;
+}
+
sub pp_dbstate { pp_nextstate(@_) }
sub pp_setstate { pp_nextstate(@_) }
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_complement { maybe_targmy(@_, \&pfixop, "~", 21) }
sub pp_negate { maybe_targmy(@_, \&real_negate) }
sub real_negate {
sub pp_close { unop(@_, "close") }
sub pp_fileno { unop(@_, "fileno") }
sub pp_umask { unop(@_, "umask") }
-sub pp_binmode { unop(@_, "binmode") }
sub pp_untie { unop(@_, "untie") }
sub pp_tied { unop(@_, "tied") }
sub pp_dbmclose { unop(@_, "dbmclose") }
sub pp_exists {
my $self = shift;
my($op, $cx) = @_;
+ my $arg;
+ if ($op->private & OPpEXISTS_SUB) {
+ # Checking for the existence of a subroutine
+ return $self->maybe_parens_func("exists",
+ $self->pp_rv2cv($op->first, 16), $cx, 16);
+ }
+ if ($op->flags & OPf_SPECIAL) {
+ # Array element, not hash element
+ return $self->maybe_parens_func("exists",
+ $self->pp_aelem($op->first, 16), $cx, 16);
+ }
return $self->maybe_parens_func("exists", $self->pp_helem($op->first, 16),
$cx, 16);
}
my($op, $cx) = @_;
my $arg;
if ($op->private & OPpSLICE) {
+ if ($op->flags & OPf_SPECIAL) {
+ # Deleting from an array, not a hash
+ return $self->maybe_parens_func("delete",
+ $self->pp_aslice($op->first, 16),
+ $cx, 16);
+ }
return $self->maybe_parens_func("delete",
$self->pp_hslice($op->first, 16),
$cx, 16);
} else {
+ if ($op->flags & OPf_SPECIAL) {
+ # Deleting from an array, not a hash
+ return $self->maybe_parens_func("delete",
+ $self->pp_aelem($op->first, 16),
+ $cx, 16);
+ }
return $self->maybe_parens_func("delete",
$self->pp_helem($op->first, 16),
$cx, 16);
my $name = $self->const_sv($op->first)->PV;
$name =~ s[/][::]g;
$name =~ s/\.pm//g;
- return "require($name)";
+ return "require $name";
} else {
$self->unop($op, $cx, "require");
}
my ($op, $cx, $lowop, $lowprec, $highop, $highprec, $blockname) = @_;
my $left = $op->first;
my $right = $op->first->sibling;
- if ($cx == 0 and is_scope($right) and $blockname) { # if ($a) {$b}
+ if ($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'}) { # $b if $a
+ } elsif ($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";
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") }
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($false))) {
+ (is_scope($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 $head . join($cuddle, "", @elsifs) . $false;
}
-sub pp_leaveloop {
+sub loop_common {
my $self = shift;
- my($op, $cx) = @_;
+ my($op, $cx, $init) = @_;
my $enter = $op->first;
my $kid = $enter->sibling;
- local($self->{'curstash'}) = $self->{'curstash'};
+ local(@$self{qw'curstash warnings hints'})
+ = @$self{qw'curstash warnings hints'};
my $head = "";
my $bare = 0;
+ my $body;
+ my $cond = undef;
+ my $out_seq = $self->{'curcop'}->cop_seq;;
if ($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;
$var = "\$" . $self->deparse($var, 1);
}
$head = "foreach $var ($ary) ";
- $kid = $kid->first->first->sibling; # skip OP_AND and OP_ITER
+ $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};
- $head = "$name (" . $self->deparse($kid->first, 1) . ") ";
- $kid = $kid->first->sibling;
+ 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
}
- # The third-to-last kid is the continue block if the pointer used
- # by `next BLOCK' points to its first OP, which happens to be the
- # the op_next of the head of the _previous_ statement.
- # Unless it's a bare loop, in which case it's last, since there's
- # no unstack or extra nextstate.
- # Except if the previous head isn't null but the first kid is
- # (because it's a nulled out nextstate in a scope), in which
- # case the head's next is advanced past the null but the nextop's
- # isn't, so we need to try nextop->next.
- my $precont;
- my $cont = $kid->first;
- if ($bare) {
- while (!null($cont->sibling)) {
- $precont = $cont;
- $cont = $cont->sibling;
- }
- } else {
- while (!null($cont->sibling->sibling->sibling)) {
- $precont = $cont;
- $cont = $cont->sibling;
+ # 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";
}
- }
- if ($precont and $ {$precont->next} == $ {$enter->nextop}
- || $ {$precont->next} == $ {$enter->nextop->next} )
- {
- my $state = $kid->first;
- my $cuddle = $self->{'cuddle'};
- my($expr, @exprs);
- for (; $$state != $$cont; $state = $state->sibling) {
- $expr = "";
- if (is_state $state) {
- $expr = $self->deparse($state, 0);
- $state = $state->sibling;
- last if null $state;
- }
- $expr .= $self->deparse($state, 0);
- push @exprs, $expr if $expr;
- }
- $kid = join(";\n", @exprs);
- $cont = $cuddle . "continue {\n\t" .
- $self->deparse($cont, 0) . "\n\b}\cK";
} else {
+ return "" if !defined $body;
$cont = "\cK";
- $kid = $self->deparse($kid, 0);
+ $body = $self->deparse($body, 0);
}
- return $head . "{\n\t" . $kid . "\n\b}" . $cont;
+ $body .= "\n";
+ # If we have say C<{my $x=2; sub x{$x}}>, the sub must go inside
+ # the loop. So we insert any subs which are due here.
+ $body .= join"", $self->seq_subs($out_seq);
+
+ return $head . "{\n\t" . $body . "\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 {
}
}
-# the aassign in-common check messes up SvCUR (always setting it
-# to a value >= 100), but it's probably safe to assume there
-# won't be any NULs in the names of my() variables. (with
-# stash variables, I wouldn't be so sure)
-sub padname_fix {
- my $str = shift;
- $str = substr($str, 0, index($str, "\0")) if index($str, "\0") != -1;
- return $str;
-}
-
sub padname {
my $self = shift;
my $targ = shift;
- my $str = $self->padname_sv($targ)->PV;
- return padname_fix($str);
+ return $self->padname_sv($targ)->PVX;
}
sub padany {
my $self = shift;
my($op, $cx) = @_;
my $gv = $self->gv_or_padgv($op);
- return $self->maybe_local($op, $cx, "\$" . $self->gv_name($gv));
+ return $self->maybe_local($op, $cx, $self->stash_variable("\$",
+ $self->gv_name($gv)));
}
sub pp_gv {
my $self = shift;
my($op, $cx) = @_;
my $gv = $self->gv_or_padgv($op);
- return "\$" . $self->gv_name($gv) . "[" . $op->private . "]";
+ return "\$" . $self->gv_name($gv) . "[" .
+ ($op->private + $self->{'arybase'}) . "]";
}
sub rv2x {
my($op, $cx, $type) = @_;
my $kid = $op->first;
my $str = $self->deparse($kid, 0);
- return $type . (is_scalar($kid) ? $str : "{$str}");
+ return $self->stash_variable($type, $str) if is_scalar($kid);
+ return $type ."{$str}";
}
sub pp_rv2sv { maybe_local(@_, rv2x(@_, "\$")) }
$left . $self->deparse($idx, 1) . $right;
}
$idx = $self->deparse($idx, 1);
+
+ # Outer parens in an array index will confuse perl
+ # if we're interpolating in a regular expression, i.e.
+ # /$x$foo[(-1)]/ is *not* the same as /$x$foo[-1]/
+ #
+ # If $self->{parens}, then an initial '(' will
+ # definitely be paired with a final ')'. If
+ # !$self->{parens}, the misleading parens won't
+ # have been added in the first place.
+ #
+ # [You might think that we could get "(...)...(...)"
+ # where the initial and final parens do not match
+ # each other. But we can't, because the above would
+ # only happen if there's an infix binop between the
+ # two pairs of parens, and *that* means that the whole
+ # expression would be parenthesized as well.]
+ #
+ $idx =~ s/^\((.*)\)$/$1/ if $self->{'parens'};
+
return "\$" . $array . $left . $idx . $right;
}
my $arrow = is_subscriptable($kid->first) ? "" : "->";
$kid = $self->deparse($kid, 24) . $arrow;
}
+
+ # Doesn't matter how many prototypes there are, if
+ # they haven't happened yet!
+ my $declared = exists $self->{'subs_declared'}{$kid};
+
my $args;
- if (defined $proto and not $amper) {
+ if ($declared and defined $proto and not $amper) {
($amper, $args) = $self->check_proto($proto, @exprs);
if ($amper eq "&") {
$args = join(", ", map($self->deparse($_, 6), @exprs));
return $prefix . $amper. $kid;
}
} else {
- if (defined $proto and $proto eq "") {
+ # glob() invocations can be translated into calls of
+ # CORE::GLOBAL::glob with an second parameter, a number.
+ # Reverse this.
+ if ($kid eq "CORE::GLOBAL::glob") {
+ $kid = "glob";
+ $args =~ s/\s*,[^,]+$//;
+ }
+
+ # It's a syntax error to call CORE::GLOBAL::foo without a prefix,
+ # so it must have been translated from a keyword call. Translate
+ # it back.
+ $kid =~ s/^CORE::GLOBAL:://;
+
+ if (!$declared) {
+ return "$kid(" . $args . ")";
+ } elsif (defined $proto and $proto eq "") {
return $kid;
} elsif (defined $proto and $proto eq "\$") {
return $self->maybe_parens_func($kid, $args, $cx, 16);
}
# character escapes, but not delimiters that might need to be escaped
-sub escape_str { # ASCII
+sub escape_str { # ASCII, UTF8
my($str) = @_;
+ $str =~ s/(.)/ord($1)>255 ? sprintf("\\x{%x}", ord($1)) : $1/eg;
$str =~ s/\a/\\a/g;
# $str =~ s/\cH/\\b/g; # \b means someting different in a regex
$str =~ s/\t/\\t/g;
return $str;
}
+# Remove backslashes which precede literal control characters,
+# to avoid creating ambiguity when we escape the latter.
+sub re_unback {
+ my($str) = @_;
+
+ # the insane complexity here is due to the behaviour of "\c\"
+ $str =~ s/(^|[^\\]|\\c\\)(?<!\\c)\\(\\\\)*(?=[\0-\031\177-\377])/$1$2/g;
+ return $str;
+}
+
sub balanced_delim {
my($str) = @_;
my @str = split //, $str;
my $sv = shift;
if (class($sv) eq "SPECIAL") {
return ('undef', '1', '0')[$$sv-1]; # sv_undef, sv_yes, sv_no
+ } elsif (class($sv) eq "NULL") {
+ return 'undef';
} elsif ($sv->FLAGS & SVf_IOK) {
- return $sv->IV;
+ return $sv->int_value;
} elsif ($sv->FLAGS & SVf_NOK) {
return $sv->NV;
- } elsif ($sv->FLAGS & SVf_ROK) {
+ } elsif ($sv->FLAGS & SVf_ROK && $sv->can("RV")) {
return "\\(" . const($sv->RV) . ")"; # constant folded
} else {
my $str = $sv->PV;
sub pp_const {
my $self = shift;
my($op, $cx) = @_;
+ if ($op->private & OPpCONST_ARYBASE) {
+ return '$[';
+ }
# if ($op->private & OPpCONST_BARE) { # trouble with `=>' autoquoting
# return $self->const_sv($op)->PV;
# }
my $sv = $self->const_sv($op);
- return const($sv);
+# return const($sv);
+ my $c = const $sv;
+ return $c =~ /^-\d/ ? $self->maybe_parens($c, $cx, 21) : $c;
}
sub dq {
my $op = shift;
my $type = $op->name;
if ($type eq "const") {
- return uninterp(escape_str(unback($self->const_sv($op)->PV)));
+ return '$[' if $op->private & OPpCONST_ARYBASE;
+ return uninterp(escape_str(unback($self->const_sv($op)->as_string)));
} elsif ($type eq "concat") {
- return $self->dq($op->first) . $self->dq($op->last);
+ my $first = $self->dq($op->first);
+ my $last = $self->dq($op->last);
+ # Disambiguate "${foo}bar", "${foo}{bar}", "${foo}[1]"
+ if ($last =~ /^[A-Z\\\^\[\]_?]/) {
+ $first =~ s/([\$@])\^$/${1}{^}/; # "${^}W" etc
+ }
+ elsif ($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 ($type eq "lc") {
sub collapse {
my(@chars) = @_;
- my($c, $str, $tr);
+ my($str, $c, $tr) = ("");
for ($c = 0; $c < @chars; $c++) {
$tr = $chars[$c];
$str .= pchr($tr);
}
@from = @newfrom;
}
- unless ($flags & OPpTRANS_DELETE) {
+ unless ($flags & OPpTRANS_DELETE || !@to) {
pop @to while $#to and $to[$#to] == $to[$#to -1];
}
my($from, $to);
my $op = shift;
my $type = $op->name;
if ($type eq "const") {
- return uninterp($self->const_sv($op)->PV);
+ return '$[' if $op->private & OPpCONST_ARYBASE;
+ return re_uninterp(escape_str(re_unback($self->const_sv($op)->as_string)));
} elsif ($type eq "concat") {
- return $self->re_dq($op->first) . $self->re_dq($op->last);
+ my $first = $self->re_dq($op->first);
+ my $last = $self->re_dq($op->last);
+ # Disambiguate "${foo}bar", "${foo}{bar}", "${foo}[1]"
+ if ($last =~ /^[A-Z\\\^\[\]_?]/) {
+ $first =~ s/([\$@])\^$/${1}{^}/;
+ }
+ elsif ($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") {
$kid = $kid->sibling;
}
if (null $kid) {
- $re = re_uninterp(escape_str($op->precomp));
+ $re = re_uninterp(escape_str(re_unback($op->precomp)));
} else {
$re = $self->deparse($kid, 1);
}
for (; !null($kid); $kid = $kid->sibling) {
push @exprs, $self->deparse($kid, 6);
}
+
+ # handle special case of split(), and split(" ") that compiles to /\s+/
+ $kid = $op->first;
+ if ($kid->flags & OPf_SPECIAL
+ && $exprs[0] eq '/\\s+/'
+ && $kid->pmflags & PMf_SKIPWHITE ) {
+ $exprs[0] = '" "';
+ }
+
$expr = "split(" . join(", ", @exprs) . ")";
if ($ary) {
return $self->maybe_parens("$ary = $expr", $cx, 7);
}
}
if (null $kid) {
- $re = re_uninterp(escape_str($op->precomp));
+ $re = re_uninterp(escape_str(re_unback($op->precomp)));
} else {
$re = $self->deparse($kid, 1);
}
=head1 SYNOPSIS
-B<perl> B<-MO=Deparse>[B<,-u>I<PACKAGE>][B<,-p>][B<,-q>][B<,-l>][B<,-s>I<LETTERS>]
- I<prog.pl>
+B<perl> B<-MO=Deparse>[B<,-u>I<PACKAGE>][B<,-p>][B<,-q>][B<,-l>]
+ [B<,-s>I<LETTERS>][B<,-x>I<LEVEL>] I<prog.pl>
=head1 DESCRIPTION
C<$x = "$y"> is not the same as C<$x = $y>: the former makes the value
of $y into a string before doing the assignment.
-=item B<-u>I<PACKAGE>
+=item B<-f>I<FILE>
-Normally, B::Deparse deparses the main code of a program, all the subs
-called by the main program (and all the subs called by them,
-recursively), and any other subs in the main:: package. To include
-subs in other packages that aren't called directly, such as AUTOLOAD,
-DESTROY, other subs called automatically by perl, and methods (which
-aren't resolved to subs until runtime), use the B<-u> option. The
-argument to B<-u> is the name of a package, and should follow directly
-after the 'u'. Multiple B<-u> options may be given, separated by
-commas. Note that unlike some other backends, B::Deparse doesn't
-(yet) try to guess automatically when B<-u> is needed -- you must
-invoke it yourself.
+Normally, B::Deparse deparses the main code of a program, and all the subs
+defined in the same file. To include subs defined in other files, pass the
+B<-f> option with the filename. You can pass the B<-f> option several times, to
+include more than one secondary file. (Most of the time you don't want to
+use it at all.) You can also use this option to include subs which are
+defined in the scope of a B<#line> directive with two parameters.
=item B<-s>I<LETTERS>
=back
+=item B<-x>I<LEVEL>
+
+Expand conventional syntax constructions into equivalent ones that expose
+their internal operation. I<LEVEL> should be a digit, with higher values
+meaning more expansion. As with B<-q>, this actually involves turning off
+special cases in B::Deparse's normal operations.
+
+If I<LEVEL> is at least 3, for loops will be translated into equivalent
+while loops with continue blocks; for instance
+
+ for ($i = 0; $i < 10; ++$i) {
+ print $i;
+ }
+
+turns into
+
+ $i = 0;
+ while ($i < 10) {
+ print $i;
+ } continue {
+ ++$i
+ }
+
+Note that in a few cases this translation can't be perfectly carried back
+into the source code -- if the loop's initializer declares a my variable,
+for instance, it won't have the correct scope outside of the loop.
+
+If I<LEVEL> is at least 7, if statements will be translated into equivalent
+expressions using C<&&>, C<?:> and C<do {}>; for instance
+
+ print 'hi' if $nice;
+ if ($nice) {
+ print 'hi';
+ }
+ if ($nice) {
+ print 'hi';
+ } else {
+ print 'bye';
+ }
+
+turns into
+
+ $nice and print 'hi';
+ $nice and do { print 'hi' };
+ $nice ? do { print 'hi' } : do { print 'bye' };
+
+Long sequences of elsifs will turn into nested ternary operators, which
+B::Deparse doesn't know how to indent nicely.
+
=back
=head1 USING B::Deparse AS A MODULE
options, like B<-u>, don't make sense for a single subroutine, so
don't pass them.
+=head2 ambient_pragmas
+
+ $deparse->ambient_pragmas(strict => 'all', '$[' => $[);
+
+The compilation of a subroutine can be affected by a few compiler
+directives, B<pragmas>. These are:
+
+=over 4
+
+=item *
+
+use strict;
+
+=item *
+
+use warnings;
+
+=item *
+
+Assigning to the special variable $[
+
+=item *
+
+use integer;
+
+=item *
+
+use bytes;
+
+=item *
+
+use utf8;
+
+=item *
+
+use re;
+
+=back
+
+Ordinarily, if you use B::Deparse on a subroutine which has
+been compiled in the presence of one or more of these pragmas,
+the output will include statements to turn on the appropriate
+directives. So if you then compile the code returned by coderef2text,
+it will behave the same way as the subroutine which you deparsed.
+
+However, you may know that you intend to use the results in a
+particular context, where some pragmas are already in scope. In
+this case, you use the B<ambient_pragmas> method to describe the
+assumptions you wish to make.
+
+The parameters it accepts are:
+
+=over 4
+
+=item strict
+
+Takes a string, possibly containing several values separated
+by whitespace. The special values "all" and "none" mean what you'd
+expect.
+
+ $deparse->ambient_pragmas(strict => 'subs refs');
+
+=item $[
+
+Takes a number, the value of the array base $[.
+
+=item bytes
+
+=item utf8
+
+=item integer
+
+If the value is true, then the appropriate pragma is assumed to
+be in the ambient scope, otherwise not.
+
+=item re
+
+Takes a string, possibly containing a whitespace-separated list of
+values. The values "all" and "none" are special. It's also permissible
+to pass an array reference here.
+
+ $deparser->ambient_pragmas(re => 'eval');
+
+
+=item warnings
+
+Takes a string, possibly containing a whitespace-separated list of
+values. The values "all" and "none" are special, again. It's also
+permissible to pass an array reference here.
+
+ $deparser->ambient_pragmas(warnings => [qw[void io]]);
+
+If one of the values is the string "FATAL", then all the warnings
+in that list will be considered fatal, just as with the B<warnings>
+pragma itself. Should you need to specify that some warnings are
+fatal, and others are merely enabled, you can pass the B<warnings>
+parameter twice:
+
+ $deparser->ambient_pragmas(
+ warnings => 'all',
+ warnings => [FATAL => qw/void io/],
+ );
+
+See L<perllexwarn> for more information about lexical warnings.
+
+=item hint_bits
+
+=item warning_bits
+
+These two parameters are used to specify the ambient pragmas in
+the format used by the special variables $^H and ${^WARNING_BITS}.
+
+They exist principally so that you can write code like:
+
+ { my ($hint_bits, $warning_bits);
+ BEGIN {($hint_bits, $warning_bits) = ($^H, ${^WARNING_BITS})}
+ $deparser->ambient_pragmas (
+ hint_bits => $hint_bits,
+ warning_bits => $warning_bits,
+ '$[' => 0 + $[
+ ); }
+
+which specifies that the ambient pragmas are exactly those which
+are in scope at the point of calling.
+
+=back
+
=head2 coderef2text
$body = $deparse->coderef2text(\&func)
=head1 AUTHOR
-Stephen McCamant <smccam@uclink4.berkeley.edu>, based on an earlier
+Stephen McCamant <smcc@CSUA.Berkeley.EDU>, based on an earlier
version by Malcolm Beattie <mbeattie@sable.ox.ac.uk>, with
contributions from Gisle Aas, James Duncan, Albert Dvornik, Hugo van
der Sanden, Gurusamy Sarathy, and Nick Ing-Simmons.
projects / p5sagit/p5-mst-13.2.git / blobdiff