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NAME
    any::feature - Backwards-compatible handling of new syntactic features

VERSION
    version 1.100840

SYNOPSIS
        use any::feature 'say';
        say 'Hello, world!';

DESCRIPTION
  THE PROBLEM
    Perl 5.10 introduces new syntactic features which you can activate and
    deactivate with the "feature" module. You want to use the "say" feature
    in a program that's supposed to run under both Perl 5.8 and 5.10. So
    your program looks like this:

        use feature 'say';
        say 'Hello, world!';

    But this only works in Perl 5.10, because there is no "feature" module
    in Perl 5.8. So you write

        use Perl6::Say;
        say 'Hello, world!';

    This works, but it's strange to force Perl 5.10 users to install
    Perl6::Say when the "say" feature is included in Perl 5.10.

  THE SOLUTION
    Use "any::feature"!

    WARNING: This is just a proof-of-concept.

    "any::feature" can be used like Perl 5.10's "feature" and will try to
    "do the right thing", regardless of whether you use Perl 5.8 or Perl
    5.10.

    At the moment, this is just a proof-of-concept and only handles the
    "say" feature. If things work out, I plan to extend it with other Perl
    5.10 features.

    The following programs should work and exhibit the same behaviour both
    in Perl 5.8 and Perl 5.10.

    This program will work:

        use any::feature 'say';
        say 'Hello, world!';

    This program will fail at compile-time:

        use any::feature 'say';
        say 'Hello, world!';

        no any::feature 'say';
        say 'Oops';

    The features are lexically scoped, which is how they work in Perl 5.10:

        {
            use any::feature 'say';
            say 'foo';
        }
        say 'bar';     # dies at compile-time

FUNCTIONS
  dispatch
    Takes as arguments a direction ("activate" or "deactivate"), a package
    name and a feature name. Activates or deactivates the given feature for
    the given package.

  activate
    Takes as arguments a package name and a feature name. Uses "dispatch()"
    to activate the given feature in the given package.

  deactivate
    Takes as arguments a package name and a feature name. Uses "dispatch()"
    to deactivate the given feature in the given package.

  import
    Takes the same arguments as Perl 5.10's "use feature" pragma. Uses
    "activate()" and "deactivate()" to do its job.

  unimport
    Takes the same arguments as Perl 5.10's "no feature" pragma. Uses
    "activate()" and "deactivate()" to do its job.

  get_effective_version
    Uses Perl::Version to get the version number of the current perl
    interpreter. This is used to decide the course of action.

  get_effective_revision
    Uses Perl::Version to get the revision number of the current perl
    interpreter. This is used to decide the course of action.

INSTALLATION
    See perlmodinstall for information and options on installing Perl
    modules.

BUGS AND LIMITATIONS
    No bugs have been reported.

    Please report any bugs or feature requests through the web interface at
    <http://rt.cpan.org/Public/Dist/Display.html?Name=any-feature>.

AVAILABILITY
    The latest version of this module is available from the Comprehensive
    Perl Archive Network (CPAN). Visit <http://www.perl.com/CPAN/> to find a
    CPAN site near you, or see <http://search.cpan.org/dist/any-feature/>.

    The development version lives at
    <http://github.com/hanekomu/any-feature/>. Instead of sending patches,
    please fork this project using the standard git and github
    infrastructure.

AUTHOR
      Marcel Gruenauer <[email protected]>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2009 by Marcel Gruenauer.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.