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NAME
    Alt - Alternate Module Implementations

SYNOPSIS
        PERL_ALT_INSTALL=OVERWRITE cpanm Alt::IO::All::Redux

DESCRIPTION
    "Alt::" is the namespace for alternate implementations of CPAN modules.

    The purpose of the Alt module is to provide documentation explaining the
    Alt concept, how it works, and guidelines for using it well.

THE PROBLEM
    For a given piece of software, CPAN only allows for one implementation
    of a given module/distribution name.

    GitHub on the other hand, is not limited this way. Any author can make a
    fork, since GitHub repos are namespaced by author id.

    On CPAN, even the author(s) of the module in question is limited by
    this, as they cannot release newer or older forks of their code, without
    introducing a new name.

THE SOLUTION
    A module "Foo::Bar" is distributed on CPAN as "Foo-Bar". It may have
    submodules like "Foo::Bar::Baz".

    To make an alternate CPAN version, leave everything exactly the same,
    except distribute the new version as "Alt-Foo-Bar-AltIdentifier".

    When a user installs your module like so:

        PERL_ALT_INSTALL=OVERWRITE cpanm Alt::Foo::Bar::better

    they will get your version of the Foo::Bar framework (Foo::Bar,
    Foo::Bar::Baz).

    Obviously, this completely overlays the old Foo::Bar install, but that's
    the whole idea. The user isn't surprised by this because they just asked
    for an Alternate implementation. If they don't like it, they can simply
    reinstall the original Foo-Bar, or try some other alternate.

ALT BEST PRACTICES
    This idea is new, and the details should be sorted out through proper
    discussions. Pull requests welcome.

    Here are the basic guidelines for best using the Alt namespace:

    Name Creation
        Names for alternate modules should be minted like this:

            "Alt-$Original_Dist_Name-$phrase"

        For instance, if MSTROUT wants to make an alternate IO-All
        distribution to have it be Moo-based, he might call it:

            Alt-IO-All-Moo

        He might also just call it:

            Alt-IO-All-MSTROUT

        By having 'Alt' at the start, it guarantees that it does not mess
        with future IO::All development. The "phrase" at the end can be
        anything unique to CPAN, but should describe the spirit of the
        alternate. If the alternate is meant to be short-lived, it can just
        be the author's CPAN id.

    Makefile.PL Changes
        Due to experience with <http://cpantesters.org/> problems, it is
        important to make your Alt module not install without explicit
        direction. You can accomplish this easily in a Makefile.PL, with
        something like this:

            my $alt = $ENV{PERL_ALT_INSTALL} || '';
            $WriteMakefileArgs{DESTDIR} =
              $alt ? $alt eq 'OVERWRITE' ? '' : $alt : 'no-install-alt';

        Similar techniques should be available for other module release
        frameworks.

    Module for CPAN Indexing
        You will need to provide a module like "Alt::IO::All::MSTROUT" so
        that CPAN will index something that can cause your distribution to
        get installed by people:

            PERL_ALT_INSTALL=OVERWRITE cpanm Alt::IO::All::MSTROUT

        Since you are adding this module, you should add some doc to it
        explaining your alternate version's improvements.

        The Alt:: module can be as simple as this:

            package Alt::IO::All::MSTROUT;
            our $VERSION = '0.01';

    no_index
        It is important to use the "no_index" directive on the modules you