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 >= 1.19 )
and the module does
not have weaken, the install will bail out
altogether with a long error encouraging the user to seek support from their
vendor (this problem happens most often in vendor-packaged Perl versions).
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' => 0;
AUTHOR¶
Adam Kennedy <adamk@cpan.org>, <
http://ali.as/>
SEE ALSO¶
Task, Scalar::Util, <
http://ali.as/>
COPYRIGHT¶
Copyright 2006 - 2009 Adam Kennedy.
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.