package Catalyst::Component::ContextClosure; use Moose::Role; use Scalar::Util 'weaken'; use namespace::autoclean; sub make_context_closure { my ($self, $closure, $ctx) = @_; weaken $ctx; return sub { $closure->($ctx, @_) }; } 1; __END__ =head1 NAME Catalyst::Component::ContextClosure - Moose Role for components which need to close over the $ctx, without leaking =head1 SYNOPSIS package MyApp::Controller::Foo; use Moose; use namespace::autoclean; BEGIN { extends 'Catalyst::Controller'; with 'Catalyst::Component::ContextClosure'; } sub some_action : Local { my ($self, $ctx) = @_; $ctx->stash(a_closure => $self->make_context_closure(sub { my ($ctx) = @_; $ctx->response->body('body set from closure'); }, $ctx); } =head1 DESCRIPTION A common problem with stashing a closure, that closes over the Catalyst context (often called C<$ctx> or C<$c>), is the circular reference it creates, as the closure holds onto a reference to context, and the context holds a reference to the closure in its stash. This creates a memory leak, unless you always carefully weaken the closures context reference. This role provides a convenience method to create closures, that closes over C<$ctx>. =head1 METHODS =head2 make_context_closure ($closure, $ctx) Returns a code reference, that will invoke C<$closure> with a weakened reference to C<$ctx>. All other parameters to the returned code reference will be passed along to C<$closure>. =head1 SEE ALSO L L L =head1 AUTHOR Florian Ragwitz Erafl@debian.orgE =head1 COPYRIGHT This library is free software. You can redistribute it and/or modify it under the same terms as Perl itself. =cut