NAME

       Alt::Assert - Assert alternate module implementation

SYNOPSIS

       Assuming there is a CPAN module Foo::Bar and mst wants to write an ALTernate called
       Alt::Foo::Bar::MSTROUT.

       In mst's Foo::Bar, there is the following line:

           use constant ALT => 'MSTROUT';

       In the alt module:

           package Alt::Foo::Bar::MSTROUT;
           use Alt::Assert; # imports assert()
           1;

       Users use mst's Foo::Bar as normal, just like they would use the original Foo::Bar:

           use Foo::Bar -various => [qw(weird import)], {API=>'things'};

       or:

           require Foo::Bar;

       If they want to assert they have the mst version, they can:

           use Foo::Bar -various => [qw(weird import)], {API=>'things'};
           use Alt::Foo::Bar::MSTROUT;

       or:

           require Foo::Bar;
           require Alt::Foo::Bar::MSTROUT;
           Alt::Foo::Bar::MSTROUT->assert;

DESCRIPTION

       Alt::Assert can be used to assert that the loaded module is the wanted alternate
       implementation. Using the Synopsis' example, there can be different Foo::Bar installed,
       either from the original distribution, or from one of the alternate ones. Each alternate
       might be slightly incompatible with the original. The existence of Alt::Foo::Bar::MSTROUT
       in the installation does not necessarily ensure that the installed Foo::Bar is from the
       same alternate distribution, since an installer can replace Foo::Bar from another
       distribution. That is why one might need to do this assertion.

SEE ALSO

       •   Alt

AUTHOR

       Ingy döt Net <ingy@cpan.org>

COPYRIGHT

       Copyright 2012-2014. Ingy döt Net.

       See <http://www.perl.com/perl/misc/Artistic.html>