NAME
    Task::Weaken - Ensure that a platform has weaken support

DESCRIPTION
    One recurring problem in modules that use Scalar::Util's "weaken"
    function is that it is not present in the pure-perl variant.

    While this isn't necesarily always a problem in a straight CPAN-based
    Perl environment, some operating system distributions only include the
    pure-Perl versions, don't include the XS version, and so weaken is then
    "missing" from the platform, despite passing a dependency on
    Scalar::Util successfully.

    Most notably this is RedHat Linux at time of writing, but other come and
    go and do the same thing, hence "recurring problem".

    The normal solution is to manually write tests in each distribution to
    ensure that "weaken" is available.

    This restores the functionality testing to a dependency you do once in
    your Makefile.PL, rather than something you have to write extra tests
    for each time you write a module.

    It should also help make the package auto-generators for the various
    operating systems play more nicely, because it introduces a dependency
    that they have to have a proper weaken in order to work.

  How this Task works
    Part of the problem seems to stem from the fact that some distributions
    continue to include modules even if they fail some of their tests.

    To get around that for this module, it will do a few dirty tricks.

    If Scalar::Util is not available at all, it will issue a normal
    dependency on the module. However, if Scalar::Util is relatively new (
    it is >= 1.14 ) and the module does not have weaken, the install will
    bail out altogether with a "platform does not support this module"
    error.

    This means that a distributor cannot just force the install, as there
    will be no Makefile at all to do the installation phase.

    This is to some degree lying, so it is somewhat debatable if this
    strategy should continue, and may be removed later.

    This distribution also contains tests to ensure that weaken is available
    using more normal methods.

    So if your module uses "weaken", you can just add the following to your
    Module::Install-based Makefile.PL (or equivalent).

      requires 'Task::Weaken';

AUTHOR
    Adam Kennedy <cpan@ali.as>, <http://ali.as/>

SEE ALSO
    Task, Scalar::Util, <http://ali.as/>

COPYRIGHT
    Copyright 2006 Adam Kennedy. All rights reserved.

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

    The full text of the license can be found in the LICENSE file included
    with this module.