/ 
Sub-Called-0.06
River stage zero No dependents
/ Sub::Called

NAME

Sub::Called - get information about how the subroutine is called

VERSION

version 0.06

SYNOPSIS

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;
    }
}

EXPORTS

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.

This subroutine is only exported on demand.

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()).

This subroutine is only exported on demand.

FUNCTIONS

with_ampersand

already_called

not_called

LIMITATIONS / TODO

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.

Subroutine References

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();

Inside a module

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";
    }
}

CONTRIBUTORS

Renee Baecker, <module at renee-baecker.de>

Curtis "Ovid" Poe, <ovid at cpan.org>

ISSUE TRACKER & CODE REPOSITORY

An issue tracker and the code repository are available at http://github.com/reneeb/Sub-Called.

AUTHOR

Renee Baecker <reneeb@cpan.org>

COPYRIGHT AND LICENSE

This software is Copyright (c) 2008 by Renee Baecker.

This is free software, licensed under:

The Artistic License 2.0 (GPL Compatible)