ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/Devel-FindRef/FindRef.pm
(Generate patch)

Comparing Devel-FindRef/FindRef.pm (file contents):
Revision 1.16 by root, Fri Sep 19 05:07:56 2008 UTC vs.
Revision 1.20 by root, Sat Dec 6 12:42:49 2008 UTC

5 5
6use XSLoader; 6use XSLoader;
7use Scalar::Util; 7use Scalar::Util;
8 8
9BEGIN { 9BEGIN {
10 our $VERSION = '1.31'; 10 our $VERSION = '1.4';
11 XSLoader::load __PACKAGE__, $VERSION; 11 XSLoader::load __PACKAGE__, $VERSION;
12} 12}
13 13
14=head1 NAME 14=head1 NAME
15 15
32the variables containing them. 32the variables containing them.
33 33
34For example, for this fragment: 34For example, for this fragment:
35 35
36 package Test; 36 package Test;
37
38 use Devel::FindRef;
39 use Scalar::Util;
37 40
38 our $var = "hi\n"; 41 our $var = "hi\n";
39 my $x = \$var; 42 my $global_my = \$var;
40 our %hash = (ukukey => \$var); 43 our %global_hash = (ukukey => \$var);
41 our $hash2 = {ukukey2 => \$var}; 44 our $global_hashref = { ukukey2 => \$var };
42 45
43 sub testsub { 46 sub testsub {
44 my $local = $hash2; 47 my $testsub_local = $global_hashref;
45 print Devel::FindRef::track \$var; 48 print Devel::FindRef::track \$var;
46 } 49 }
47 50
48 testsub; 51
52 my $closure = sub {
53 my $closure_var = \$_[0];
54 Scalar::Util::weaken (my $weak_ref = \$var);
55 testsub;
56 };
57
58 $closure->($var);
49 59
50The output is as follows (or similar to this, in case I forget to update 60The output is as follows (or similar to this, in case I forget to update
51the manpage after some changes): 61the manpage after some changes):
52 62
53 SCALAR(0x814ece8) is 63 SCALAR(0x7cc888) [refcount 6] is
64 +- referenced by REF(0x8abcc8) [refcount 1], which is
65 | in the lexical '$closure_var' in CODE(0x8abc50) [refcount 4], which is
66 | +- the closure created at tst:18.
67 | +- referenced by REF(0x7d3c58) [refcount 1], which is
68 | | in the lexical '$closure' in CODE(0x7ae530) [refcount 2], which is
69 | | +- the containing scope for CODE(0x8ab430) [refcount 3], which is
70 | | | in the global &Test::testsub.
71 | | +- the main body of the program.
72 | +- in the lexical '&' in CODE(0x7ae530) [refcount 2], which was seen before.
73 +- referenced by REF(0x7cc7c8) [refcount 1], which is
74 | in the lexical '$global_my' in CODE(0x7ae530) [refcount 2], which was seen before.
54 +- in the global $Test::var. 75 +- in the global $Test::var.
55 +- referenced by REF(0x814f9e4), which is 76 +- referenced by REF(0x7cc558) [refcount 1], which is
56 | in the lexical '$x' in CODE(0x814ed78), which is
57 | the containing scope for CODE(0x820c4b0), which is
58 | in the global &Test::testsub.
59 +- referenced by REF(0x814ed6c), which is
60 | in the member 'ukukey' of HASH(0x81da20c), which is 77 | in the member 'ukukey2' of HASH(0x7ae140) [refcount 2], which is
78 | +- referenced by REF(0x8abad0) [refcount 1], which is
79 | | in the lexical '$testsub_local' in CODE(0x8ab430) [refcount 3], which was seen before.
80 | +- referenced by REF(0x8ab4f0) [refcount 1], which is
81 | in the global $Test::global_hashref.
82 +- referenced by REF(0x7ae518) [refcount 1], which is
83 | in the member 'ukukey' of HASH(0x7d3bb0) [refcount 1], which is
61 | in the global %Test::hash. 84 | in the global %Test::global_hash.
62 +- referenced by REF(0x814ec28), which is 85 +- referenced by REF(0x7ae2f0) [refcount 1], which is
63 | not found anywhere I looked :( 86 a temporary on the stack.
64 +- referenced by REF(0x814eb44), which is
65 in the member 'ukukey2' of HASH(0x814f99c), which is
66 +- referenced by REF(0x820c450), which is
67 | in the lexical '$local' in CODE(0x820c4b0), which was seen before.
68 +- referenced by REF(0x820c204), which is
69 in the global $Test::hash2.
70 87
71It is a bit convoluted to read, but basically it says that the value 88It is a bit convoluted to read, but basically it says that the value
72stored in C<$var> can be found: 89stored in C<$var> is referenced by:
73 90
74=over 4 91=over 4
75 92
76=item - in some variable C<$x> whose origin is not known (I frankly have no 93=item - the lexical C<$closure_var> (0x8abcc8), which is inside an instantiated
77idea why, hints accepted). 94closure, which in turn is used quite a bit.
78 95
79=item - in the hash element with key C<ukukey> in the hash stored in C<%Test::hash>. 96=item - the package-level lexical C<$global_my>.
80 97
81=item - in the global variable named C<$Test::var>. 98=item - the global package variable named C<$Test::var>.
82 99
83=item - in the hash element C<ukukey2>, in the hash in the my variable 100=item - the hash element C<ukukey2>, in the hash in the my variable
84C<$local> in the sub C<Test::testsub> and also in the hash referenced by 101C<$testsub_local> in the sub C<Test::testsub> and also in the hash
102C<$referenced by Test::hash2>.
103
104=item - the hash element with key C<ukukey> in the hash stored in
85C<$Test::hash2>. 105C<%Test::hash>.
106
107=item - some anonymous mortalised reference on the stack (which is caused
108by calling C<track> with the expression C<\$var>, which creates the
109reference).
86 110
87=back 111=back
112
113And all these account for six reference counts.
114
88 115
89=head1 EXPORTS 116=head1 EXPORTS
90 117
91None. 118None.
92 119
103This is the function you most often use. 130This is the function you most often use.
104 131
105=cut 132=cut
106 133
107sub find($); 134sub find($);
135
136sub _f($) {
137 "$_[0] [refcount " . (_refcnt $_[0]) . "]"
138}
108 139
109sub track { 140sub track {
110 my ($ref, $depth) = @_; 141 my ($ref, $depth) = @_;
111 @_ = (); 142 @_ = ();
112 143
120 151
121 if ($depth) { 152 if ($depth) {
122 my (@about) = find $$refref; 153 my (@about) = find $$refref;
123 if (@about) { 154 if (@about) {
124 for my $about (@about) { 155 for my $about (@about) {
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";
146 $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, ""); 177 $track->(\$ref, $depth || $ENV{PERL_DEVEL_FINDREF_DEPTH} || 10, "");
147 $buf 178 $buf
148} 179}
149 180
150=item @references = Devel::FindRef::find $ref 181=item @references = Devel::FindRef::find $ref
191 222
192=head1 AUTHOR 223=head1 AUTHOR
193 224
194Marc Lehmann <pcg@goof.com>. 225Marc Lehmann <pcg@goof.com>.
195 226
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 227=head1 COPYRIGHT AND LICENSE
203 228
204Copyright (C) 2007 by Marc Lehmann. 229Copyright (C) 2007, 2008 by Marc Lehmann.
205 230
206This library is free software; you can redistribute it and/or modify 231This 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, 232it 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. 233at your option, any later version of Perl 5 you may have available.
209 234

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines