NAME

Devel::UseAnyFunc - Import any of several equivalent functions

SYNOPSIS

  use Devel::UseAnyFunc 'url_esc', HTML::Mason::Escapes => 'url_escape', 
                                   URI::Escape          => 'uri_escape',
                                   CGI::Util            => 'escape',
                                   PApp::HTML           => 'escape_uri';
  
  # I don't care which of the above I get, as long as it works locally.
  print url_esc( $my_address );

DESCRIPTION

Devel::UseAnyFunc allows you to request any one of several equivalent functions from separate modules without forcing a dependancy on a specific one.

Motivation

As an example, many different modules provide essentially-equivalent URL escaping functions. A developer writing a CGI script might use Devel::UseAnyFunc to allow their script to run on a variety of different hosts, as long as it has at least one of the relevant modules is installed.

Operation

To take advantage of this module, use it, passing the name of the function you would like, followed by a list of pairs of a package name and a function name.

Each of the listed packages is tested in turn, in the order provided. If that module can be loaded with require, then the associated function is selected; if not, then the next one is tested. If none of the modules is found, it croaks and lists the modules it tried.

Whichever function is selected, it is installed in the callers namespace under the name provided by the first argument to the use statement. (Internally, the same type of symbol-table manipulation is used as in Exporter.)

Diagnostics

If you set $DIGANOSTICS to a true value before using the module, it will warn a series of diagnostic messages that explain which modules it's testing and which one it settles on.

  BEGIN { $Devel::UseAnyFunc::DIGANOSTICS = 1 }
  use Devel::UseAnyFunc ...

Subcassing

You may easily subclass this packge in order to provde a specialized "Any" module.

  package My::AnyFoo;
  use strict;
  use Devel::UseAnyFunc '-isasubclass';
  
  sub import { 
    my ( $self, $name, @sources ) = @_;
    ... adjust the contents of $name and @sources as needed...
    $self->SUPER::import( $name, @sources );
  }

CREDITS AND COPYRIGHT

Developed by Matthew Simon Cavalletto at Evolution Softworks. More free Perl software is available at www.evoscript.org.

You may contact the author directly at evo@cpan.org or simonm@cavalletto.org.

To report bugs via the CPAN web tracking system, go to http://rt.cpan.org/NoAuth/Bugs.html?Dist=Devel-UseAnyFunc or send mail to Dist=Devel-UseAnyFuncE#rt.cpan.org, replacing # with @.

Copyright 2003 Matthew Simon Cavalletto.

You may use, modify, and distribute this software under the same terms as Perl.