README
1NAME
2 Task::Weaken - Ensure that a platform has weaken support
3
4DESCRIPTION
5 One recurring problem in modules that use Scalar::Util's "weaken"
6 function is that it is not present in the pure-perl variant.
7
8 While this isn't necesarily always a problem in a straight CPAN-based
9 Perl environment, some operating system distributions only include the
10 pure-Perl versions, don't include the XS version, and so weaken is then
11 "missing" from the platform, despite passing a dependency on
12 Scalar::Util successfully.
13
14 Most notably this is RedHat Linux at time of writing, but other come and
15 go and do the same thing, hence "recurring problem".
16
17 The normal solution is to manually write tests in each distribution to
18 ensure that "weaken" is available.
19
20 This restores the functionality testing to a dependency you do once in
21 your Makefile.PL, rather than something you have to write extra tests
22 for each time you write a module.
23
24 It should also help make the package auto-generators for the various
25 operating systems play more nicely, because it introduces a dependency
26 that they have to have a proper weaken in order to work.
27
28 How this Task works
29 Part of the problem seems to stem from the fact that some distributions
30 continue to include modules even if they fail some of their tests.
31
32 To get around that for this module, it will do a few dirty tricks.
33
34 If Scalar::Util is not available at all, it will issue a normal
35 dependency on the module. However, if Scalar::Util is relatively new (
36 it is >= 1.19 ) and the module does not have weaken, the install will
37 bail out altogether with a long error encouraging the user to seek
38 support from their vendor (this problem happens most often in
39 vendor-packaged Perl versions).
40
41 This distribution also contains tests to ensure that weaken is available
42 using more normal methods.
43
44 So if your module uses "weaken", you can just add the following to your
45 Module::Install-based Makefile.PL (or equivalent).
46
47 requires 'Task::Weaken' => 0;
48
49AUTHOR
50 Adam Kennedy <adamk@cpan.org>, <http://ali.as/>
51
52SEE ALSO
53 Task, Scalar::Util, <http://ali.as/>
54
55COPYRIGHT
56 Copyright 2006 - 2009 Adam Kennedy.
57
58 This program is free software; you can redistribute it and/or modify it
59 under the same terms as Perl itself.
60
61 The full text of the license can be found in the LICENSE file included
62 with this module.
63
64