# phpman > info > Sub::Install

Sub::[Install(3pm)](https://www.chedong.com/phpMan.php/man/Install/3pm/markdown)     User Contributed Perl Documentation    Sub::[Install(3pm)](https://www.chedong.com/phpMan.php/man/Install/3pm/markdown)

NAME
       [Sub::Install](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall/markdown) - install subroutines into packages easily

VERSION
       version 0.928

SYNOPSIS
         use [Sub::Install](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall/markdown);

         [Sub::Install::install_sub](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall%3A%3Ainstallsub/markdown)({
           code => sub { ... },
           into => $package,
           as   => $subname
         });

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

FUNCTIONS
   install_sub
         [Sub::Install::install_sub](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall%3A%3Ainstallsub/markdown)({
          code => \&subroutine,
          into => "[Finance::Shady](https://www.chedong.com/phpMan.php/perldoc/Finance%3A%3AShady/markdown)",
          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](https://www.chedong.com/phpMan.php/perldoc/Finance%3A%3AShady/markdown)" . '::' . "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](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall/markdown) will try to find the name of the given code ref and use
       that as "as".

       That means that this code:

         [Sub::Install::install_sub](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall%3A%3Ainstallsub/markdown)({
           code => 'twitch',
           from => '[Person::InPain](https://www.chedong.com/phpMan.php/perldoc/Person%3A%3AInPain/markdown)',
           into => '[Person::Teenager](https://www.chedong.com/phpMan.php/perldoc/Person%3A%3ATeenager/markdown)',
           as   => 'dance',
         });

       is the same as:

         package [Person::Teenager](https://www.chedong.com/phpMan.php/perldoc/Person%3A%3ATeenager/markdown);

         [Sub::Install::install_sub](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall%3A%3Ainstallsub/markdown)({
           code => [Person::InPain](https://www.chedong.com/phpMan.php/perldoc/Person%3A%3AInPain/markdown)->can('twitch'),
           as   => 'dance',
         });

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

   install_installers
       This routine is provided to allow [Sub::Install](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall/markdown) compatibility with
       [Sub::Installer](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstaller/markdown).  It installs "install_sub" and "reinstall_sub" methods
       into the package named by its argument.

        [Sub::Install::install_installers](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall%3A%3Ainstallinstallers/markdown)('[Code::Builder](https://www.chedong.com/phpMan.php/perldoc/Code%3A%3ABuilder/markdown)'); # just for us, please
        [Code::Builder](https://www.chedong.com/phpMan.php/perldoc/Code%3A%3ABuilder/markdown)->install_sub({ name => $code_ref });

        [Sub::Install::install_installers](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall%3A%3Ainstallinstallers/markdown)('UNIVERSAL'); # feeling lucky, punk?
        [Anything::At::All](https://www.chedong.com/phpMan.php/perldoc/Anything%3A%3AAt%3A%3AAll/markdown)->install_sub({ name => $code_ref });

       The installed installers are similar, but not identical, to those
       provided by [Sub::Installer](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstaller/markdown).  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](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstaller/markdown)'s "install_sub" will not eval strings into code,
       but will look for named code in the calling package.

EXPORTS
       [Sub::Install](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall/markdown) exports "install_sub" and "reinstall_sub" only if they are
       requested.

   exporter
       [Sub::Install](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall/markdown) 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](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall/markdown)'s own consumption.  Instead,
       consider [Sub::Exporter](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AExporter/markdown).

SEE ALSO
       [Sub::Installer](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstaller/markdown)
           This module is (obviously) a reaction to Damian Conway's
           [Sub::Installer](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstaller/markdown), 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.

       [Sub::Exporter](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AExporter/markdown)
           This is a complete Exporter.pm replacement, built atop
           [Sub::Install](https://www.chedong.com/phpMan.php/perldoc/Sub%3A%3AInstall/markdown).

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

AUTHOR
       Ricardo SIGNES <<rjbs@cpan.org>>

COPYRIGHT AND LICENSE
       This software is copyright (c) 2005 by Ricardo SIGNES.

       This is free software; you can redistribute it and/or modify it under
       the same terms as the Perl 5 programming language system itself.

perl v5.32.0                      2020-12-23                 Sub::[Install(3pm)](https://www.chedong.com/phpMan.php/man/Install/3pm/markdown)
