[p5sagit/Devel-GlobalDestruction.git] / lib / Devel / GlobalDestruction.pm

#!/usr/bin/perl

package Devel::GlobalDestruction;

use strict;
use warnings;

use XSLoader;

our $VERSION = '0.04';

use Sub::Exporter -setup => {
	exports => [ qw(in_global_destruction) ],
	groups  => { default => [ -all ] },
};

if (defined ${^GLOBAL_PHASE}) {
    eval 'sub in_global_destruction () { ${^GLOBAL_PHASE} eq q[DESTRUCT] }';
}
else {
    XSLoader::load(__PACKAGE__, $VERSION);
}

__PACKAGE__

__END__

=pod

=head1 NAME

Devel::GlobalDestruction - Expose the flag which marks global
destruction.

=head1 SYNOPSIS

	package Foo;
	use Devel::GlobalDestruction;

	use namespace::clean; # to avoid having an "in_global_destruction" method

	sub DESTROY {
		return if in_global_destruction;

		do_something_a_little_tricky();
	}

=head1 DESCRIPTION

Perl's global destruction is a little tricky to deal with WRT finalizers
because it's not ordered and objects can sometimes disappear.

Writing defensive destructors is hard and annoying, and usually if global
destruction is happenning you only need the destructors that free up non
process local resources to actually execute.

For these constructors you can avoid the mess by simply bailing out if global
destruction is in effect.

=head1 EXPORTS

This module uses L<Sub::Exporter> so the exports may be renamed, aliased, etc.

=over 4

=item in_global_destruction

Returns true if the interpreter is in global destruction. In perl 5.14+, this
returns C<${^GLOBAL_PHASE} eq 'DESTRUCT'>, and on earlier perls, it returns the
current value of C<PL_dirty>.

=back

=head1 VERSION CONTROL

This module is maintained using Darcs. You can get the latest version from
L<http://nothingmuch.woobling.org/code>, and use C<darcs send> to commit
changes.

=head1 AUTHORS

Yuval Kogman E<lt>nothingmuch@woobling.orgE<gt>

Florian Ragwitz E<lt>rafl@debian.orgE<gt>

Jesse Luehrs E<lt>doy@tozt.netE<gt>

=head1 COPYRIGHT

	Copyright (c) 2008 Yuval Kogman. All rights reserved
	This program is free software; you can redistribute
	it and/or modify it under the same terms as Perl itself.

=cut
Commit	Line	Data
a91e8a78	1	#!/usr/bin/perl
	2
	3	package Devel::GlobalDestruction;
	4
	5	use strict;
	6	use warnings;
	7
53e46d40	8	use XSLoader;
a91e8a78	9
aaa7f60f	10	our $VERSION = '0.04';
a91e8a78	11
a91e8a78	12	use Sub::Exporter -setup => {
	13	exports => [ qw(in_global_destruction) ],
	14	groups => { default => [ -all ] },
	15	};
	16
eaac10b5	17	if (defined ${^GLOBAL_PHASE}) {
3790e928	18	eval 'sub in_global_destruction () { ${^GLOBAL_PHASE} eq q[DESTRUCT] }';
	19	}
	20	else {
	21	XSLoader::load(__PACKAGE__, $VERSION);
	22	}
	23
a91e8a78	24	__PACKAGE__
	25
	26	__END__
	27
	28	=pod
	29
	30	=head1 NAME
	31
761f3ee2	32	Devel::GlobalDestruction - Expose the flag which marks global
a91e8a78	33	destruction.
	34
	35	=head1 SYNOPSIS
	36
	37	package Foo;
	38	use Devel::GlobalDestruction;
	39
	40	use namespace::clean; # to avoid having an "in_global_destruction" method
	41
	42	sub DESTROY {
	43	return if in_global_destruction;
	44
	45	do_something_a_little_tricky();
	46	}
	47
	48	=head1 DESCRIPTION
	49
	50	Perl's global destruction is a little tricky to deal with WRT finalizers
	51	because it's not ordered and objects can sometimes disappear.
	52
	53	Writing defensive destructors is hard and annoying, and usually if global
	54	destruction is happenning you only need the destructors that free up non
	55	process local resources to actually execute.
	56
	57	For these constructors you can avoid the mess by simply bailing out if global
	58	destruction is in effect.
	59
	60	=head1 EXPORTS
	61
	62	This module uses L<Sub::Exporter> so the exports may be renamed, aliased, etc.
	63
	64	=over 4
	65
	66	=item in_global_destruction
	67
761f3ee2	68	Returns true if the interpreter is in global destruction. In perl 5.14+, this
	69	returns C<${^GLOBAL_PHASE} eq 'DESTRUCT'>, and on earlier perls, it returns the
	70	current value of C<PL_dirty>.
a91e8a78	71
	72	=back
	73
	74	=head1 VERSION CONTROL
	75
	76	This module is maintained using Darcs. You can get the latest version from
	77	L<http://nothingmuch.woobling.org/code>, and use C<darcs send> to commit
	78	changes.
	79
ec94b9e1	80	=head1 AUTHORS
a91e8a78	81
	82	Yuval Kogman E<lt>nothingmuch@woobling.orgE<gt>
	83
ec94b9e1	84	Florian Ragwitz E<lt>rafl@debian.orgE<gt>
ec94b9e1	85
aaa7f60f	86	Jesse Luehrs E<lt>doy@tozt.netE<gt>
aaa7f60f	87
a91e8a78	88	=head1 COPYRIGHT
	89
	90	Copyright (c) 2008 Yuval Kogman. All rights reserved
	91	This program is free software; you can redistribute
	92	it and/or modify it under the same terms as Perl itself.
	93
	94	=cut
	95
	96