If you know what use does (perldoc -f use, perldoc -f require) ... an example is File::Spec (a core module) 
package File::Spec;

use strict;
use vars qw(@ISA $VERSION);

$VERSION = '0.86';

my %module = (MacOS   => 'Mac',
              MSWin32 => 'Win32',
              os2     => 'OS2',
              VMS     => 'VMS',
              epoc    => 'Epoc',
              NetWare => 'Win32', # Yes, File::Spec::Win32 works on Ne
+tWare.
              dos     => 'OS2',   # Yes, File::Spec::OS2 works on DJGP
+P.
              cygwin  => 'Cygwin');


my $module = $module{$^O} || 'Unix';

require "File/Spec/$module.pm";
@ISA = ("File::Spec::$module");

1;

__END__

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Sure you don't need to actually require/use anything, but @ISA is @ISA ;)(perldoc perlmod, perldoc perlvar ...)

MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
** The third rule of perl club is a statement of fact: pod is sexy.

In reply to Re: Using a 'package' as a 'module', and choosing at runtime? by PodMaster
in thread Using a 'package' as a 'module', and choosing at runtime? by blueflashlight

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