NAME¶
Alt - Alternate Module Implementations
SYNOPSIS¶
cpanm Alt::IO::All::crackfueled
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:
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.
WHENCE ALT?¶
The Alt- concept was thought up by Ingy as he tried to figure out how to revamp
the somewhat popular IO::All and YAML.pm modules. Alternates can now be
released and alpha/beta tested, while the originals remain stable.
When Alt-IO-All-new is "community approved" it can replace IO-All. If
people want the old code, they can can install Alt-IO-All-old.
GUIDELINES¶
This idea is new, and the details should be sorted out through proper
discussions. Pull requests welcome.
Here are the basic guidelines for 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
make it even more crack fueled, he might call it:
Alt-IO-All-crackfueled
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.
- 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:
cpanm Alt::IO::All::MSTROUT
Since you are adding this module, you should add some doc to it explaining
your Alternate version's improvements.
- Versioning
- The VERSION of the module you are providing an alternate version of should
be the same as the original module at the time you release the alternate.
This will make it play well with others.
To use the IO::All example, if MSTROUT releases Alt-IO-All-MSTROUT when
IO::All is at version '0.46', his IO::All module should have VERSION =
'0.46', but his Alt::IO::All::MSTROUT could be VERSION '0.000005'. This
should make the dist be Alt-IO-All-MSTROUT-0.000005.
If another module wants his version of IO::All, it should list
Alt::IO::All::MSTROUT 0.000005 as a prereq, and then "use IO::All
0.46;" in the code.
- no_index
- It is important to use the "no_index" directive on the modules
you are providing an alternative to. This is especially important if you
are the author of the original, as PAUSE will reindex CPAN to your Alt-
version which defeats the purpose. Even if you are not the same author, it
will make your index reports not show failures.
- Other Concerns
- If you have em, I(ngy) would like to know them. Discuss on #toolchain on
irc.perl.org for now.
AUTHOR¶
Ingy doet Net <ingy@cpan.org>
COPYRIGHT¶
Copyright 2012-2014. Ingy doet Net.
See <
http://www.perl.com/perl/misc/Artistic.html>