Performance optimisation in assert, suggested by Tim Bunce

[perl5.git] / lib / version.pm

#!perl -w
package version;

use 5.005_04;
use strict;

use vars qw(@ISA $VERSION $CLASS *declare *qv);

$VERSION = 0.77;

$CLASS = 'version';

# Preloaded methods go here.
sub import {
    no strict 'refs';
    my ($class) = shift;

    # Set up any derived class
    unless ($class eq 'version') {
	local $^W;
	*{$class.'::declare'} =  \&version::declare;
	*{$class.'::qv'} = \&version::qv;
    }

    my %args;
    if (@_) { # any remaining terms are arguments
	map { $args{$_} = 1 } @_
    }
    else { # no parameters at all on use line
    	%args = 
	(
	    qv => 1,
	    'UNIVERSAL::VERSION' => 1,
	);
    }
    
    my $callpkg = caller();
    
    if (exists($args{declare})) {
	*{$callpkg."::declare"} = 
	    sub {return $class->declare(shift) }
	  unless defined(&{$callpkg.'::declare'});
    }

    if (exists($args{qv})) {
	*{$callpkg."::qv"} =
	    sub {return $class->qv(shift) }
	  unless defined(&{"$callpkg\::qv"});
    }

    if (exists($args{'VERSION'})) {
	*{$callpkg."::VERSION"} = \&version::_VERSION;
    }
}

1;