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Comparing Devel-FindRef/FindRef.pm (file contents):
Revision 1.16 by root, Fri Sep 19 05:07:56 2008 UTC vs.
Revision 1.28 by root, Sat Apr 13 06:29:39 2013 UTC

1package Devel::FindRef; 1package Devel::FindRef;
2 2
3no warnings; # I hate warning nazis 3use common::sense;
4use strict;
5 4
6use XSLoader; 5use XSLoader;
7use Scalar::Util; 6use Scalar::Util;
8 7
9BEGIN { 8BEGIN {
10 our $VERSION = '1.31'; 9 our $VERSION = '1.422';
11 XSLoader::load __PACKAGE__, $VERSION; 10 XSLoader::load __PACKAGE__, $VERSION;
12} 11}
13 12
14=head1 NAME 13=head1 NAME
15 14
32the variables containing them. 31the variables containing them.
33 32
34For example, for this fragment: 33For example, for this fragment:
35 34
36 package Test; 35 package Test;
36
37 use Devel::FindRef;
38 use Scalar::Util;
37 39
38 our $var = "hi\n"; 40 our $var = "hi\n";
39 my $x = \$var; 41 my $global_my = \$var;
40 our %hash = (ukukey => \$var); 42 our %global_hash = (ukukey => \$var);
41 our $hash2 = {ukukey2 => \$var}; 43 our $global_hashref = { ukukey2 => \$var };
42 44
43 sub testsub { 45 sub testsub {
44 my $local = $hash2; 46 my $testsub_local = $global_hashref;
45 print Devel::FindRef::track \$var; 47 print Devel::FindRef::track \$var;
46 } 48 }
47 49
48 testsub; 50
51 my $closure = sub {
52 my $closure_var = \$_[0];
53 Scalar::Util::weaken (my $weak_ref = \$var);
54 testsub;
55 };
56
57 $closure->($var);
49 58
50The output is as follows (or similar to this, in case I forget to update 59The output is as follows (or similar to this, in case I forget to update
51the manpage after some changes): 60the manpage after some changes):
52 61
53 SCALAR(0x814ece8) is 62 SCALAR(0x7cc888) [refcount 6] is
63 +- referenced by REF(0x8abcc8) [refcount 1], which is
64 | the lexical '$closure_var' in CODE(0x8abc50) [refcount 4], which is
65 | +- the closure created at tst:18.
66 | +- referenced by REF(0x7d3c58) [refcount 1], which is
67 | | the lexical '$closure' in CODE(0x7ae530) [refcount 2], which is
68 | | +- the containing scope for CODE(0x8ab430) [refcount 3], which is
69 | | | the global &Test::testsub.
70 | | +- the main body of the program.
71 | +- the lexical '&' in CODE(0x7ae530) [refcount 2], which was seen before.
72 +- referenced by REF(0x7cc7c8) [refcount 1], which is
73 | the lexical '$global_my' in CODE(0x7ae530) [refcount 2], which was seen before.
54 +- in the global $Test::var. 74 +- the global $Test::var.
55 +- referenced by REF(0x814f9e4), which is 75 +- referenced by REF(0x7cc558) [refcount 1], which is
56 | in the lexical '$x' in CODE(0x814ed78), which is 76 | the member 'ukukey2' of HASH(0x7ae140) [refcount 2], which is
57 | the containing scope for CODE(0x820c4b0), which is 77 | +- referenced by REF(0x8abad0) [refcount 1], which is
58 | in the global &Test::testsub. 78 | | the lexical '$testsub_local' in CODE(0x8ab430) [refcount 3], which was seen before.
79 | +- referenced by REF(0x8ab4f0) [refcount 1], which is
80 | the global $Test::global_hashref.
59 +- referenced by REF(0x814ed6c), which is 81 +- referenced by REF(0x7ae518) [refcount 1], which is
60 | in the member 'ukukey' of HASH(0x81da20c), which is 82 | the member 'ukukey' of HASH(0x7d3bb0) [refcount 1], which is
61 | in the global %Test::hash. 83 | the global %Test::global_hash.
62 +- referenced by REF(0x814ec28), which is 84 +- referenced by REF(0x7ae2f0) [refcount 1], which is
63 | not found anywhere I looked :( 85 a temporary on the stack.
64 +- referenced by REF(0x814eb44), which is
65 in the member 'ukukey2' of HASH(0x814f99c), which is
66 +- referenced by REF(0x820c450), which is
67 | in the lexical '$local' in CODE(0x820c4b0), which was seen before.
68 +- referenced by REF(0x820c204), which is
69 in the global $Test::hash2.
70 86
71It is a bit convoluted to read, but basically it says that the value 87It is a bit convoluted to read, but basically it says that the value
72stored in C<$var> can be found: 88stored in C<$var> is referenced by:
73 89
74=over 4 90=over 4
75 91
76=item - in some variable C<$x> whose origin is not known (I frankly have no 92=item - the lexical C<$closure_var> (0x8abcc8), which is inside an instantiated
77idea why, hints accepted). 93closure, which in turn is used quite a bit.
78 94
79=item - in the hash element with key C<ukukey> in the hash stored in C<%Test::hash>. 95=item - the package-level lexical C<$global_my>.
80 96
81=item - in the global variable named C<$Test::var>. 97=item - the global package variable named C<$Test::var>.
82 98
83=item - in the hash element C<ukukey2>, in the hash in the my variable 99=item - the hash element C<ukukey2>, in the hash in the my variable
84C<$local> in the sub C<Test::testsub> and also in the hash referenced by 100C<$testsub_local> in the sub C<Test::testsub> and also in the hash
101C<$referenced by Test::hash2>.
102
103=item - the hash element with key C<ukukey> in the hash stored in
85C<$Test::hash2>. 104C<%Test::hash>.
105
106=item - some anonymous mortalised reference on the stack (which is caused
107by calling C<track> with the expression C<\$var>, which creates the
108reference).
86 109
87=back 110=back
111
112And all these account for six reference counts.
113
88 114
89=head1 EXPORTS 115=head1 EXPORTS
90 116
91None. 117None.
92 118
103This is the function you most often use. 129This is the function you most often use.
104 130
105=cut 131=cut
106 132
107sub find($); 133sub find($);
134
135sub _f($) {
136 "$_[0] [refcount " . (_refcnt $_[0]) . "]"
137}
108 138
109sub track { 139sub track {
110 my ($ref, $depth) = @_; 140 my ($ref, $depth) = @_;
111 @_ = (); 141 @_ = ();
112 142
120 150
121 if ($depth) { 151 if ($depth) {
122 my (@about) = find $$refref; 152 my (@about) = find $$refref;
123 if (@about) { 153 if (@about) {
124 for my $about (@about) { 154 for my $about (@about) {
155 $about->[0] =~ s/([^\x20-\x7e])/sprintf "\\{%02x}", ord $1/ge;
125 $buf .= "$indent" . (@about > 1 ? "+- " : " ") . $about->[0]; 156 $buf .= "$indent" . (@about > 1 ? "+- " : "") . $about->[0];
126 if (@$about > 1) { 157 if (@$about > 1) {
127 if ($seen{ref2ptr $about->[1]}++) { 158 if ($seen{ref2ptr $about->[1]}++) {
128 $buf .= " $about->[1], which was seen before.\n"; 159 $buf .= " " . (_f $about->[1]) . ", which was seen before.\n";
129 } else { 160 } else {
130 $buf .= " $about->[1], which is\n"; 161 $buf .= " " . (_f $about->[1]) . ", which is\n";
131 $track->(\$about->[1], $depth - 1, $about == $about[-1] ? "$indent " : "$indent| "); 162 $track->(\$about->[1], $depth - 1, $about == $about[-1] ? "$indent " : "$indent| ");
132 } 163 }
133 } else { 164 } else {
134 $buf .= ".\n"; 165 $buf .= ".\n";
135 } 166 }
140 } else { 171 } else {
141 $buf .= "$indent not referenced within the search depth.\n"; 172 $buf .= "$indent not referenced within the search depth.\n";
142 } 173 }
143 }; 174 };
144 175
145 $buf .= "$ref is\n"; 176 $buf .= (_f $ref) . " is\n";
177
146 $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, ""); 178 $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, "");
147 $buf 179 $buf
148} 180}
149 181
150=item @references = Devel::FindRef::find $ref 182=item @references = Devel::FindRef::find $ref
160=cut 192=cut
161 193
162sub find($) { 194sub find($) {
163 my ($about, $excl) = &find_; 195 my ($about, $excl) = &find_;
164 my %excl = map +($_ => undef), @$excl; 196 my %excl = map +($_ => undef), @$excl;
165 grep !exists $excl{ref2ptr $_->[1]}, @$about 197 grep !($#$_ && exists $excl{ref2ptr $_->[1]}), @$about
166} 198}
167 199
168=item $ref = Devel::FindRef::ptr2ref $integer 200=item $ref = Devel::FindRef::ptr2ref $integer
169 201
170Sometimes you know (from debugging output) the address of a perl scalar 202Sometimes you know (from debugging output) the address of a perl value you
171you are interested in (e.g. C<HASH(0x176ff70)>). This function can be used 203are interested in (e.g. C<HASH(0x176ff70)>). This function can be used to
172to turn the address into a reference to that scalar. It is quite safe to 204turn the address into a reference to that value. It is quite safe to call
173call on valid addresses, but extremely dangerous to call on invalid ones. 205on valid addresses, but extremely dangerous to call on invalid ones. I<No
206checks whatsoever will be done>, so don't use this unless you really know
207the value is the address of a valid perl value.
174 208
175 # we know that HASH(0x176ff70) exists, so turn it into a hashref: 209 # we know that HASH(0x176ff70) exists, so turn it into a hashref:
176 my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70; 210 my $ref_to_hash = Devel::FindRef::ptr2ref 0x176ff70;
177 211
178=item $ref = Devel::FindRef::ref2ptr $reference 212=item $ptr = Devel::FindRef::ref2ptr $reference
179 213
180The opposite of C<ptr2ref>, above: returns the internal address of the 214The opposite of C<ptr2ref>, above: returns the internal address of the
181value pointed to by the passed reference. I<No checks whatsoever will be 215value pointed to by the passed reference. This function is safe to call on
182done>, so don't use this. 216anything, and returns the same value taht a normal reference would if used
217in a numeric context.
183 218
184=back 219=back
185 220
186=head1 ENVIRONMENT VARIABLES 221=head1 ENVIRONMENT VARIABLES
187 222
191 226
192=head1 AUTHOR 227=head1 AUTHOR
193 228
194Marc Lehmann <pcg@goof.com>. 229Marc Lehmann <pcg@goof.com>.
195 230
196=head1 BUGS
197
198Only code values, arrays, hashes, scalars and magic are being looked at.
199
200This is a quick hack only.
201
202=head1 COPYRIGHT AND LICENSE 231=head1 COPYRIGHT AND LICENSE
203 232
204Copyright (C) 2007 by Marc Lehmann. 233Copyright (C) 2007, 2008 by Marc Lehmann.
205 234
206This library is free software; you can redistribute it and/or modify 235This library is free software; you can redistribute it and/or modify
207it under the same terms as Perl itself, either Perl version 5.8.8 or, 236it under the same terms as Perl itself, either Perl version 5.8.8 or,
208at your option, any later version of Perl 5 you may have available. 237at your option, any later version of Perl 5 you may have available.
209 238

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