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Module Version: 0.926   Source   Latest Release: Sub-Install-0.928


Sub::Install - install subroutines into packages easily


version 0.926


  use Sub::Install;

    code => sub { ... },
    into => $package,
    as   => $subname


This module makes it easy to install subroutines into packages without the unslightly mess of no strict or typeglobs lying about where just anyone can see them.



   code => \&subroutine,
   into => "Finance::Shady",
   as   => 'launder',

This routine installs a given code reference into a package as a normal subroutine. The above is equivalent to:

  no strict 'refs';
  *{"Finance::Shady" . '::' . "launder"} = \&subroutine;

If into is not given, the sub is installed into the calling package.

If code is not a code reference, it is looked for as an existing sub in the package named in the from parameter. If from is not given, it will look in the calling package.

If as is not given, and if code is a name, as will default to code. If as is not given, but if code is a code ref, Sub::Install will try to find the name of the given code ref and use that as as.

That means that this code:

    code => 'twitch',
    from => 'Person::InPain',
    into => 'Person::Teenager',
    as   => 'dance',

is the same as:

  package Person::Teenager;

    code => Person::InPain->can('twitch'),
    as   => 'dance',


This routine behaves exactly like "install_sub", but does not emit a warning if warnings are on and the destination is already defined.


This routine is provided to allow Sub::Install compatibility with Sub::Installer. It installs install_sub and reinstall_sub methods into the package named by its argument.

 Sub::Install::install_installers('Code::Builder'); # just for us, please
 Code::Builder->install_sub({ name => $code_ref });

 Sub::Install::install_installers('UNIVERSAL'); # feeling lucky, punk?
 Anything::At::All->install_sub({ name => $code_ref });

The installed installers are similar, but not identical, to those provided by Sub::Installer. They accept a single hash as an argument. The key/value pairs are used as the as and code parameters to the install_sub routine detailed above. The package name on which the method is called is used as the into parameter.

Unlike Sub::Installer's install_sub will not eval strings into code, but will look for named code in the calling package.


Sub::Install exports install_sub and reinstall_sub only if they are requested.


Sub::Install has a never-exported subroutine called exporter, which is used to implement its import routine. It takes a hashref of named arguments, only one of which is currently recognize: exports. This must be an arrayref of subroutines to offer for export.

This routine is mainly for Sub::Install's own consumption. Instead, consider Sub::Exporter.



This module is (obviously) a reaction to Damian Conway's Sub::Installer, which does the same thing, but does it by getting its greasy fingers all over UNIVERSAL. I was really happy about the idea of making the installation of coderefs less ugly, but I couldn't bring myself to replace the ugliness of typeglobs and loosened strictures with the ugliness of UNIVERSAL methods.


This is a complete replacement, built atop Sub::Install.


Ricardo Signes, <>

Several of the tests are adapted from tests that shipped with Damian Conway's Sub-Installer distribution.


Please report any bugs or feature requests through the web interface at I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.


Copyright 2005-2006 Ricardo Signes, All Rights Reserved.

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

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