| Perl-AtEndOfScope documentation | Contained in the Perl-AtEndOfScope distribution. |
Perl::AtEndOfScope - run some code when a variable goes out of scope
use Perl::AtEndOfScope;
use Cwd;
{
my $restorecwd=Perl::AtEndOfScope->new( sub{chdir $_[0]}, getcwd );
chdir '/path/to/some/directory';
...
}
# now we are back to the old cwd
# or better using the undocumented "chdir FILEHANDLE"
use Perl::AtEndOfScope;
{
my $restorecwd=Perl::AtEndOfScope->new( sub{chdir $_[0]},
do {opendir my $d, '.'; $d} );
chdir '/path/to/some/directory';
...
}
# now we are back to the old cwd
It's often necessary to do some cleanup at the end of a scope. This module creates a Perl object and executes arbitrary code when the object goes out of scope.
the constructor. The code reference passed in $sub is called with @args as parameter list when the object is destroyed.
While $sub is executed the following variables are preserved:
$@, $a, $b, $_, $., $!, $^E, $?
This list can grow in future versions.
$sub is executed within an eval block. You can check
$Perl::AtEndOfFile::EXC
to see if an exception has been thrown by it. $Perl::AtEndOfScope::EXC is not stringified.
If multiple Perl::AtEndOfScope objects are destroyed at the same time only the last exception thrown by one of them is saved.
the destructor.
Not an Exporter.
Torsten Foertsch, <torsten.foertsch@gmx.net>
Copyright (C) 2005-2008 by Torsten Foertsch
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
| Perl-AtEndOfScope documentation | Contained in the Perl-AtEndOfScope distribution. |
package Perl::AtEndOfScope; use 5.008; use strict; use warnings; our $VERSION = '0.03'; our $EXC; sub new { my $class=shift; my $I=[@_]; return bless $I=>(ref($class)||$class); } sub DESTROY { my ($fn, @args)=@{$_[0]}; undef $EXC; { local ($@, $a, $b, $_, $., $!, $^E, $?); eval {$fn->(@args)}; $EXC=$@; } } 1; __END__