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Sub::Exporter::ForMethods.3pm

NAME

Sub::Exporter::ForMethods - helper routines for using Sub::Exporter to build methods

VERSION

version 0.091970

SYNOPSIS

In an exporting library:

   package Method::Builder;
 
   use Sub::Exporter::ForMethods qw(method_installer);
 
   use Sub::Exporter -setup => {
     exports   => [ method => \'_method_generator' ],
     installer => method_installer,
   };
 
   sub _method_generator {
     my ($self, $name, $arg, $col) = @_;
     return sub { ... };
   };
 
 

In an importing library:

   package Vehicle::Autobot;
   use Method::Builder method => { -as => 'transform' };
 
 

DESCRIPTION

The synopsis section, above, looks almost indistinguishable from any other use of Sub::Exporter, apart from the use of "method_installer". It is nearly indistinguishable in behavior, too. The only change is that subroutines exported from Method::Builder into named slots in Vehicle::Autobot will be wrapped in a subroutine called "Vehicle::Autobot::transform". This will insert a named frame into stack traces to aid in debugging.

More importantly (for the author, anyway), they will not be removed by namespace::autoclean. This makes the following code work:

   package MyLibrary;
 
   use Math::Trig qw(tan);         # uses Exporter.pm
   use String::Truncate qw(trunc); # uses Sub::Exporter's defaults
 
   use Sub::Exporter::ForMethods qw(method_installer);
   use Mixin::Linewise { installer => method_installer }, qw(read_file);
 
   use namespace::autoclean;
 
   ...
 
   1;
 
 

After MyLibrary is compiled, "namespace::autoclean" will remove "tan" and "trunc" as foreign contaminants, but will leave "read_file" in place. It will also remove "method_installer", an added win.

EXPORTS

Sub::Exporter::ForMethods offers only one routine for export, and it may also be called by its full package name:

method_installer

This routine returns an installer suitable for use as the "installer" argument to Sub::Exporter. It updates the "\@to_export" argument to wrap all code that will be installed by name in a named subroutine, then passes control to the default Sub::Exporter installer.

AUTHOR

   Ricardo Signes <rjbs@cpan.org>
 
 

COPYRIGHT AND LICENSE

This software is copyright (c) 2009 by Ricardo Signes.

This is free software; you can redistribute it and/or modify it under the same terms as perl itself.