# B::Deparse.pm
-# Copyright (c) 1998 Stephen McCamant. All rights reserved.
+# Copyright (c) 1998,1999 Stephen McCamant. All rights reserved.
# This module is free software; you can redistribute and/or modify
# it under the same terms as Perl itself.
package B::Deparse;
use Carp 'cluck';
use B qw(class main_root main_start main_cv svref_2object opnumber
- OPf_WANT OPf_WANT_VOID OPf_WANT_SCALAR OPf_WANT_LIST
- OPpENTERSUB_AMPER OPf_KIDS OPpLVAL_INTRO
- OPf_SPECIAL OPpSLICE OPpCONST_BARE OPf_REF OPf_STACKED
- OPpENTERSUB_AMPER OPpTRANS_SQUASH OPpTRANS_DELETE
- OPpTRANS_COMPLEMENT SVf_IOK SVf_NOK SVf_ROK SVf_POK
- PMf_ONCE PMf_SKIPWHITE PMf_CONST PMf_KEEP PMf_GLOBAL PMf_CONTINUE
- PMf_EVAL PMf_LOCALE PMf_MULTILINE PMf_SINGLELINE PMf_FOLD PMf_EXTENDED
- );
-$VERSION = 0.561;
+ OPf_WANT OPf_WANT_VOID OPf_WANT_SCALAR OPf_WANT_LIST
+ OPf_KIDS OPf_REF OPf_STACKED OPf_SPECIAL
+ OPpLVAL_INTRO OPpENTERSUB_AMPER OPpSLICE OPpCONST_BARE
+ OPpTRANS_SQUASH OPpTRANS_DELETE OPpTRANS_COMPLEMENT
+ SVf_IOK SVf_NOK SVf_ROK SVf_POK
+ PMf_KEEP PMf_GLOBAL PMf_CONTINUE PMf_EVAL PMf_ONCE
+ PMf_MULTILINE PMf_SINGLELINE PMf_FOLD PMf_EXTENDED);
+$VERSION = 0.57;
use strict;
# Changes between 0.50 and 0.51:
# Changes between 0.51 and 0.52:
# - added pp_threadsv (special variables under USE_THREADS)
# - added documentation
-# Changes between 0.52 and 0.53
+# 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
+# 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
+# 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
+# Changes between 0.55 and 0.56:
# - tested on base/*.t, cmd/*.t, comp/*.t, io/*.t
# - fixed $# on non-lexicals broken in last big rewrite
# - added temporary fix for change in opcode of OP_STRINGIFY
# - print doubled rv2gv (a bug) as `*{*GV}' instead of illegal `**GV'
# - added semicolons at the ends of blocks
# - added -l `#line' declaration option -- fixes cmd/subval.t 27,28
+# Changes between 0.56 and 0.561:
+# - fixed multiply-declared my var in pp_truncate (thanks to Sarathy)
+# - used new B.pm symbolic constants (done by Nick Ing-Simmons)
+# Changes between 0.561 and 0.57:
+# - stylistic changes to symbolic constant stuff
+# - handled scope in s///e replacement code
+# - added unquote option for expanding "" into concats, etc.
+# - split method and proto parts of pp_entersub into separate functions
+# - various minor cleanups
# Todo:
# - {} around variables in strings ("${var}letters")
# base/lex.t 25-27
# comp/term.t 11
-# - generate symbolic constants directly from core source
# - left/right context
+# - recognize `use utf8', `use integer', etc
+# - handle swash-based utf8 tr/// (ick, looks hard)
# - avoid semis in one-statement blocks
# - associativity of &&=, ||=, ?:
# - ',' => '=>' (auto-unquote?)
# - break long lines ("\r" as discretionary break?)
+# - ANSI color syntax highlighting?
# - 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?
#
# parens: -p
# linenums: -l
+# unquote: -q
# cuddle: ` ' or `\n', depending on -sC
# A little explanation of how precedence contexts and associativity
}
}
-
sub walk_tree {
my($op, $sub) = @_;
$sub->($op);
$self->{'parens'} = 1;
} elsif ($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);
}
my $self = shift;
my($op, $cx) = @_;
# cluck if class($op) eq "NULL";
+# return $self->$ {\$op->ppaddr}($op, $cx);
my $meth = $op->ppaddr;
return $self->$meth($op, $cx);
}
return join("\n", @lines);
}
-
sub deparse_sub {
my $self = shift;
my $cv = shift;
return join("", @text) . ".";
}
-# 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 is_scope {
my $op = shift;
return $op->ppaddr eq "pp_leave" || $op->ppaddr eq "pp_scope"
return ($op->ppaddr eq "pp_rv2sv" or
$op->ppaddr eq "pp_padsv" or
$op->ppaddr eq "pp_gv" or # only in array/hash constructs
- !null($op->first) && $op->first->ppaddr eq "pp_gvsv");
+ $op->flags & OPf_KIDS && !null($op->first)
+ && $op->first->ppaddr eq "pp_gvsv");
}
sub maybe_parens {
}
}
-
sub maybe_local {
my $self = shift;
my($op, $cx, $text) = @_;
}
}
-
sub unop {
my $self = shift;
my($op, $cx, $name, $prec, $flags) = (@_, 0, 0);
sub pp_length { unop(@_, "length") }
sub pp_ord { unop(@_, "ord") }
sub pp_chr { unop(@_, "chr") }
-sub pp_ucfirst { unop(@_, "ucfirst") }
-sub pp_lcfirst { unop(@_, "lcfirst") }
-sub pp_uc { unop(@_, "uc") }
-sub pp_lc { unop(@_, "lc") }
-sub pp_quotemeta { unop(@_, "quotemeta") }
sub pp_each { unop(@_, "each") }
sub pp_values { unop(@_, "values") }
my($op, $cx) = @_;
my $kid = $op->first;
$kid = $kid->first if $kid->ppaddr eq "pp_rv2gv"; # <$fh>
- if ($kid->ppaddr eq "pp_rv2gv") {
- $kid = $kid->first;
- }
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 { dq_unop(@_, "quotemeta") }
+
sub loopex {
my $self = shift;
my ($op, $cx, $name) = @_;
} else {
return "truncate $fh, $len";
}
-
}
sub indirop {
# (because it's a nulled out nextstate in a scope), in which
# case the head's next is advanced past the null but the nextop's
# isn't, so we need to try nextop->next.
- my($cont, $precont);
+ my $precont;
+ my $cont = $kid->first;
if ($bare) {
- $cont = $kid->first;
while (!null($cont->sibling)) {
$precont = $cont;
$cont = $cont->sibling;
}
} else {
- $cont = $kid->first;
while (!null($cont->sibling->sibling->sibling)) {
$precont = $cont;
$cont = $cont->sibling;
sub pp_leavetry {
my $self = shift;
return "eval {\n\t" . $self->pp_leave(@_) . "\n\b}";
-}
+}
-my $OP_CONST = opnumber("const");
-my $OP_STRINGIFY = opnumber("stringify");
+BEGIN { eval "sub OP_CONST () {" . opnumber("const") . "}" }
+BEGIN { eval "sub OP_STRINGIFY () {" . opnumber("stringify") . "}" }
-# XXX need a better way to do this
sub pp_null {
my $self = shift;
my($op, $cx) = @_;
if (class($op) eq "OP") {
- return "'???'" if $op->targ == $OP_CONST; # old value is lost
+ return "'???'" if $op->targ == OP_CONST; # old value is lost
} elsif ($op->first->ppaddr eq "pp_pushmark") {
return $self->pp_list($op, $cx);
} elsif ($op->first->ppaddr eq "pp_enter") {
return $self->pp_leave($op, $cx);
- } elsif ($op->targ == $OP_STRINGIFY) {
+ } elsif ($op->targ == OP_STRINGIFY) {
return $self->dquote($op);
} elsif (!null($op->first->sibling) and
$op->first->sibling->ppaddr eq "pp_readline" and
}
}
+# 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 $targ = shift;
return ($op->flags & OPf_WANT) == OPf_WANT_SCALAR;
}
-sub pp_entersub {
+sub want_list {
+ my $op = shift;
+ return ($op->flags & OPf_WANT) == OPf_WANT_LIST;
+}
+
+sub method {
my $self = shift;
my($op, $cx) = @_;
- my $prefix = "";
- my $amper = "";
- my $proto = undef;
- my $simple = 0;
- my($kid, $args, @exprs);
- if (not null $op->first->sibling) { # method
- $kid = $op->first->sibling; # skip pushmark
- my $obj = $self->deparse($kid, 24);
+ my $kid = $op->first->sibling; # skip pushmark
+ my($meth, $obj, @exprs);
+ if ($kid->ppaddr eq "pp_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->first;
+ $kid = $kid->first->sibling; # skip pushmark
+ $obj = $kid;
$kid = $kid->sibling;
- for (; not null $kid->sibling; $kid = $kid->sibling) {
+ for (; not null $kid; $kid = $kid->sibling) {
push @exprs, $self->deparse($kid, 6);
}
- my $meth = $kid->first;
- if ($meth->ppaddr eq "pp_const") {
- $meth = $meth->sv->PV; # needs to be bare
- } else {
- $meth = $self->deparse($meth, 1);
+ } else {
+ $obj = $kid;
+ $kid = $kid->sibling;
+ for (; not null $kid->sibling; $kid = $kid->sibling) {
+ push @exprs, $self->deparse($kid, 6);
}
- $args = join(", ", @exprs);
- $kid = $obj . "->" . $meth;
- if ($args) {
- return $kid . "(" . $args . ")"; # parens mandatory
+ $meth = $kid->first;
+ }
+ $obj = $self->deparse($obj, 24);
+ if ($meth->ppaddr eq "pp_const") {
+ $meth = $meth->sv->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 {
- return $kid; # toke.c fakes parens
- }
+ $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->ppaddr =~ /pp_(s?refgen|undef)/) {
+ push @reals, $self->deparse($arg, 6);
+ } else {
+ return "&";
+ }
+ } elsif ($chr eq "*") {
+ if ($arg->ppaddr =~ /^pp_s?refgen$/
+ and $arg->first->first->ppaddr eq "pp_rv2gv")
+ {
+ $real = $arg->first->first; # skip refgen, null
+ if ($real->first->ppaddr eq "pp_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 ($arg->ppaddr =~ /^pp_s?refgen$/ and
+ !null($real = $arg->first) and
+ ($chr eq "\$" && is_scalar($real->first)
+ or ($chr eq "\@"
+ && $real->first->sibling->ppaddr
+ =~ /^pp_(rv2|pad)av$/)
+ or ($chr eq "%"
+ && $real->first->sibling->ppaddr
+ =~ /^pp_(rv2|pad)hv$/)
+ #or ($chr eq "&" # This doesn't work
+ # && $real->first->ppaddr eq "pp_rv2cv")
+ or ($chr eq "*"
+ && $real->first->ppaddr eq "pp_rv2gv")))
+ {
+ push @reals, $self->deparse($real, 6);
+ } else {
+ return "&";
+ }
+ }
+ }
}
- # else, not a method
+ 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) {
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) . "}";
if (class($gv->CV) ne "SPECIAL") {
$proto = $gv->CV->PV if $gv->CV->FLAGS & SVf_POK;
}
- $simple = 1;
+ $simple = 1; # only calls of named functions can be prototyped
$kid = $self->deparse($kid, 24);
} elsif (is_scalar $kid->first) {
$amper = "&";
$prefix = "";
$kid = $self->deparse($kid, 24) . "->";
}
+ my $args;
if (defined $proto and not $amper) {
- my($arg, $real);
- my $doneok = 0;
- my @args = @exprs;
- my @reals;
- my $p = $proto;
- $p =~ s/([^\\]|^)([@%])(.*)$/$1$2/;
- while ($p) {
- $p =~ s/^ *([\\]?[\$\@&%*]|;)//;
- my $chr = $1;
- if ($chr eq "") {
- undef $proto if @args;
- } elsif ($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 {
- undef $proto;
- }
- } elsif ($chr eq "&") {
- if ($arg->ppaddr =~ /pp_(s?refgen|undef)/) {
- push @reals, $self->deparse($arg, 6);
- } else {
- undef $proto;
- }
- } elsif ($chr eq "*") {
- if ($arg->ppaddr =~ /^pp_s?refgen$/
- and $arg->first->first->ppaddr eq "pp_rv2gv")
- {
- $real = $arg->first->first; # skip refgen, null
- if ($real->first->ppaddr eq "pp_gv") {
- push @reals, $self->deparse($real, 6);
- } else {
- push @reals, $self->deparse($real->first, 6);
- }
- } else {
- undef $proto;
- }
- } elsif (substr($chr, 0, 1) eq "\\") {
- $chr = substr($chr, 1);
- if ($arg->ppaddr =~ /^pp_s?refgen$/ and
- !null($real = $arg->first) and
- ($chr eq "\$" && is_scalar($real->first)
- or ($chr eq "\@"
- && $real->first->sibling->ppaddr
- =~ /^pp_(rv2|pad)av$/)
- or ($chr eq "%"
- && $real->first->sibling->ppaddr
- =~ /^pp_(rv2|pad)hv$/)
- #or ($chr eq "&" # This doesn't work
- # && $real->first->ppaddr eq "pp_rv2cv")
- or ($chr eq "*"
- && $real->first->ppaddr eq "pp_rv2gv")))
- {
- push @reals, $self->deparse($real, 6);
- } else {
- undef $proto;
- }
- }
- }
- }
- undef $proto if $p and !$doneok;
- undef $proto if @args;
- $args = join(", ", @reals);
- $amper = "";
- unless (defined $proto) {
- $amper = "&";
+ ($amper, $args) = $self->check_proto($proto, @exprs);
+ if ($amper eq "&") {
$args = join(", ", map($self->deparse($_, 6), @exprs));
}
} else {
} elsif ($c eq $close) {
$cnt--;
if ($cnt < 0) {
+ # qq()() isn't ")("
$fail = 1;
last;
}
}
}
-
sub const {
my $sv = shift;
if (class($sv) eq "SPECIAL") {
- return ('undef', '1', '0')[$$sv-1];
+ return ('undef', '1', '0')[$$sv-1]; # sv_undef, sv_yes, sv_no
} elsif ($sv->FLAGS & SVf_IOK) {
return $sv->IV;
} elsif ($sv->FLAGS & SVf_NOK) {
return "\\(" . const($sv->RV) . ")"; # constant folded
} else {
my $str = $sv->PV;
- if ($str =~ /[^ -~]/) { # ASCII
+ if ($str =~ /[^ -~]/) { # ASCII for non-printing
return single_delim("qq", '"', uninterp escape_str unback $str);
} else {
- $str =~ s/\\/\\\\/g;
- return single_delim("q", "'", $str);
+ return single_delim("q", "'", unback $str);
}
}
}
sub dquote {
my $self = shift;
- my $op = shift;
+ my($op, $cx) = shift;
+ return $self->deparse($op->first->sibling, $cx) if $self->{'unquote'};
# skip ex-stringify, pushmark
return single_delim("qq", '"', $self->dq($op->first->sibling));
}
-# OP_STRINGIFY is a listop, but it only ever has one arg (?)
+# OP_STRINGIFY is a listop, but it only ever has one arg
sub pp_stringify { dquote(@_) }
# tr/// and s/// (and tr[][], tr[]//, tr###, etc)
return $self->re_dq($kid);
}
-
# osmic acid -- see osmium tetroxide
my %matchwords;
$repl = $repl->first;
$flags .= "e";
}
- $repl = $self->dq($repl);
+ 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));
=over 4
+=item B<-l>
+
+Add '#line' declarations to the output based on the line and file
+locations of the original code.
+
=item B<-p>
Print extra parentheses. Without this option, B::Deparse includes
which probably isn't what you intended (the C<'???'> is a sign that
perl optimized away a constant value).
+=item B<-q>
+
+Expand double-quoted strings into the corresponding combinations of
+concatenation, uc, ucfirst, lc, lcfirst, quotemeta, and join. For
+instance, print
+
+ print "Hello, $world, @ladies, \u$gentlemen\E, \u\L$me!";
+
+as
+
+ print 'Hello, ' . $world . ', ' . join($", @ladies) . ', '
+ . ucfirst($gentlemen) . ', ' . ucfirst(lc $me . '!');
+
+Note that the expanded form represents the way perl handles such
+constructions internally -- this option actually turns off the reverse
+translation that B::Deparse usually does. On the other hand, note that
+C<$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>
Normally, B::Deparse deparses the main code of a program, all the subs
(yet) try to guess automatically when B<-u> is needed -- you must
invoke it yourself.
-=item B<-l>
-
-Add '#line' declarations to the output based on the line and file
-locations of the original code.
-
=item B<-s>I<LETTERS>
Tweak the style of B::Deparse's output. At the moment, only one style
=head1 AUTHOR
-Stephen McCamant <alias@mcs.com>, based on an earlier version by
-Malcolm Beattie <mbeattie@sable.ox.ac.uk>.
+Stephen McCamant <smccam@uclink4.berkeley.edu>, based on an earlier
+version by Malcolm Beattie <mbeattie@sable.ox.ac.uk>.
=cut
https://perl5.git.perl.org / perl5.git / commitdiff