NAME

Hook::AfterRuntime - Run code at the end of the compiling scope's runtime.

DESCRIPTION

Useful for creating modules that need a behavior to be added when a module that uses them completes its runtime. Like B::Hooks::EndOfScope except it triggers for run-time instead of compile-time.

An example where it might be handy:

#!/usr/bin/perl
use strict;
use warnings;
use Moose;

...

# It would be nice not to need this....
__PACKAGE__->make_immutable;

SYNOPSYS

MooseX/AutoImmute.pm

package MooseX::AutoImmute;
use strict;
use warnings;
use Hook::AfterRuntime;

sub import {
    my $class = shift;
    my $caller = caller;
    eval "package $caller; use Moose; 1" || die $@;
    after_runtime { $caller->make_immutable }
}

1;

t/mytest.t

#!/usr/bin/perl
use strict;
use warnings;
use MooseX::AutoImmute;

....

#EOF
# Package is now immutable automatically

CAVEATS

It is important to understand how Hook::AfterRuntime works in order to know its limitations. When you use a module that calls after_runtime() in its import() method, after_runtime() will inject code directly after your import statement:

import MooseX::AutoImmute;

becomes:

import MooseX::AutoImmute; my $__ENDRUNXXXXXXXX = Hook::AfterRuntime->new($id);

This creates a Hook::AfterRuntime object in the current scope. This object's id is used to reference the code provided to after_runtime() in MooseX::AutoImmute()'s import() method. When the object falls out of scope the DESTROY() method kicks in and calls the referenced code. This occurs at the end of the file when 'use' is called at the package level.

EDGE CASES

Loading in a scope other than package level:

If you use the 'use' directive on a level other than the package level, the behavior will trigger when the end of the scope is reached. If that is a subroutine then it will trigger at the end of EVERY call to that subroutine. You really should not import a class using Hook::AfterRuntime outside the package level scope.

package XXX;

sub thing {
    # Happens at compile time
    use Object::Using::AfterRuntime;

    # At runtime the hook behavior triggers here!
}

# hook behavior has not triggered

thing()

# Hook behavior has triggered

1;

require, and use class ();

When require and use class () are used the import method is not called,
thus the hook is never installed.

class->import

The hook affects the code that is currently compiling. calling
class->import happens after the compilation phase. You must wrap the
statement in a BEGIN {} to call import manually. Failure to do this will
result in the hook triggering in the wrong class, or not at all.

USER WARNING

When you write a class that depends on this hook you should insert the following warning into the docs:

This class uses Hook::AfterRuntime, it MUST be imported at the package level at compile time. This means 'use MODULE' or 'BEGIN { require MODULE; MODULE->import() }'. Failure to use one of these correct forms will result in a missing hook and unpredictable behavior.

SEE ALSO

B::Hooks::EndOfScope

Does almost the same thing, except it is triggered after compile-time instead of run-time.

FENNEC PROJECT

This module is part of the Fennec project. See Fennec for more details. Fennec is a project to develop an extensible and powerful testing framework. Together the tools that make up the Fennec framework provide a potent testing environment.

The tools provided by Fennec are also useful on their own. Sometimes a tool created for Fennec is useful outside the creator framework. Such tools are turned into their own projects. This is one such project.

Fennec - The core framework

The primary Fennec project that ties them all together.

AUTHORS

Chad Granum exodist7@gmail.com

COPYRIGHT AND LICENSE

Copyright (C) 2010-2018 Chad Granum

Hook-AfterRuntime is free software, you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

Hook-AfterRuntime is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the license for more details.

cpanm Hook::AfterRuntime

perl -MCPAN -e shell
install Hook::AfterRuntime