| Filter::EOF(3pm) | User Contributed Perl Documentation | Filter::EOF(3pm) |
Filter::EOF - Run a callback after a file has been compiled
0.04
package MyPackage;
use warnings;
use strict;
use Filter::EOF;
sub import {
my ($class, @args) = @_;
my $caller = scalar caller;
# set the COMPILE_TIME package var to a false value
# when the file was compiled
Filter::EOF->on_eof_call(sub {
no strict 'refs';
${ $caller . '::COMPILE_TIME' } = 0;
});
# set the COMPILE_TIME package var to a true value when
# we start compiling it.
{ no strict 'refs';
${ $caller . '::COMPILE_TIME' } = 1;
}
}
1;
...
package MyUsingPackage;
use warnings;
use strict;
our $COMPILE_TIME;
use MyPackage;
# prints 'yes'
BEGIN { print +( $COMPILE_TIME ? 'yes' : 'no' ), "\n" }
# prints 'no'
print +( $COMPILE_TIME ? 'yes' : 'no' ), "\n";
1;
This module utilises Perl's source filters to provide you with a mechanism to run some code after a file using your module has been processed.
Currently, only a function equivalent of the "on_eof_call" method is provided for export.
use Filter::EOF qw( on_eof_call );
sub import {
my ($class) = @_;
...
on_eof_call { ... };
}
...
Call this method in your own "import" method to register a code reference that should be called when the file "use"ing yours was compiled.
The code reference will get a scalar reference as first argument to an empty string. if you change this string to something else, it will be appended at the end of the source.
# call C<some_function()> after runtime.
Filter->on_eof_call(sub {
my $append = shift;
$$append .= '; some_function(); 1;';
});
You can optionally import the "on_eof_call" function into your namespace.
You can find the example mentioned in "SYNOPSIS" in the distribution directory "examples/synopsis/".
Filter::Call::Util, "Exporting without using Exporter's import method" in Exporter
Robert 'phaylon' Sedlacek - "<rs@474.at>". Many thanks to Matt S Trout for the idea and inspirations on this module.
This program is free software; you can redistribute it and/or modify it under the same terms as perl itself.
| 2022-10-13 | perl v5.34.0 |