Sub::Called - get information about how the subroutine is called
version 0.06
use Sub::Called; sub test { if( Sub::Called::with_ampersand() ){ print "you called this subroutine this way: &test\n", "note that this disables prototypes!\n"; } } use Sub::Called 'already_called', 'not_called'; sub user { unless (already_called) { # only gets called once My::Fixtures::Users->load; } ... } sub schema { if ( not_called ) { # setup schema } else { return $schema; } }
There are no subroutines exported by default, but you can export all subroutines explicitly
use Sub::Called qw(with_ampersand already_called not_called);
already_called
This function must be called from inside a subroutine. It will return false if the subroutine has not yet been called. It will only return false once.
This subroutine is only exported on demand.
not_called
This function must be called from inside a subroutine. It returns the opposite value of already_called. Aside from this, there is no difference. You may find aesthetically more pleasing.
with_ampersand
This function must be called from inside a subroutine. It returns 1 if the subroutine was called with an ampersand (e.g. &subroutine()).
&subroutine()
There are limitations and I don't know if I can solve these "problems". So this section is also named "TODO". If you know a solution for any of these limitations, please let me know.
It seems that there are some problems with subroutine references.
This may not work:
sub test2 { if( Sub::Called::with_ampersand() ){ die "die hard"; } }; my $sub2 = main->can( 'test2' ); &$sub2();
If you call subroutines in a module but outside any subroutine (so the subroutine calls are executed when the module is loaded), I cannot give a correct answer ;-)
package Check; use strict; use warnings; use Sub::Called qw(with_ampersand); &test; sub test { if( with_ampersand() ){ print "yada yada yada\n"; } }
Renee Baecker, <module at renee-baecker.de>
<module at renee-baecker.de>
Curtis "Ovid" Poe, <ovid at cpan.org>
<ovid at cpan.org>
An issue tracker and the code repository are available at http://github.com/reneeb/Sub-Called.
Renee Baecker <reneeb@cpan.org>
This software is Copyright (c) 2008 by Renee Baecker.
This is free software, licensed under:
The Artistic License 2.0 (GPL Compatible)
To install Sub::Called, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Sub::Called
CPAN shell
perl -MCPAN -e shell install Sub::Called
For more information on module installation, please visit the detailed CPAN module installation guide.