1 package Devel::GlobalDestruction;
8 use Sub::Exporter::Progressive -setup => {
9 exports => [ qw(in_global_destruction) ],
10 groups => { default => [ -all ] },
13 # we run 5.14+ - everything is in core
15 if (defined ${^GLOBAL_PHASE}) {
16 eval 'sub in_global_destruction () { ${^GLOBAL_PHASE} eq q[DESTRUCT] }; 1'
19 # try to load the xs version if it was compiled
23 XSLoader::load(__PACKAGE__, $VERSION);
26 # the eval already installed everything, nothing to do
29 # internally, PL_main_start is nulled immediately before entering global destruction
30 # and we can use B to detect that. It will also be null before the main runloop starts,
31 # so we check install a CHECK if needed to detect that.
33 my $started = !B::main_start()->isa(q[B::NULL]);
35 eval 'CHECK { $started = 1 }; 1'
38 eval 'sub in_global_destruction () { $started && B::main_start()->isa(q[B::NULL]) }; 1'
42 1; # keep require happy
49 Devel::GlobalDestruction - Expose the flag which marks global
55 use Devel::GlobalDestruction;
57 use namespace::clean; # to avoid having an "in_global_destruction" method
60 return if in_global_destruction;
62 do_something_a_little_tricky();
67 Perl's global destruction is a little tricky to deal with WRT finalizers
68 because it's not ordered and objects can sometimes disappear.
70 Writing defensive destructors is hard and annoying, and usually if global
71 destruction is happenning you only need the destructors that free up non
72 process local resources to actually execute.
74 For these constructors you can avoid the mess by simply bailing out if global
75 destruction is in effect.
79 This module uses L<Sub::Exporter::Progressive> so the exports may be renamed,
80 aliased, etc. if L<Sub::Exporter> is present.
84 =item in_global_destruction
86 Returns true if the interpreter is in global destruction. In perl 5.14+, this
87 returns C<${^GLOBAL_PHASE} eq 'DESTRUCT'>, and on earlier perls, it returns the
88 current value of C<PL_dirty>.
94 Yuval Kogman E<lt>nothingmuch@woobling.orgE<gt>
96 Florian Ragwitz E<lt>rafl@debian.orgE<gt>
98 Jesse Luehrs E<lt>doy@tozt.netE<gt>
100 Peter Rabbitson E<lt>ribasushi@cpan.orgE<gt>
102 Arthur Axel 'fREW' Schmidt E<lt>frioux@gmail.comE<gt>
104 Elizabeth Mattijsen E<lt>liz@dijkmat.nlE<gt>
108 Copyright (c) 2008 Yuval Kogman. All rights reserved
109 This program is free software; you can redistribute
110 it and/or modify it under the same terms as Perl itself.