package as;

sub import {
    my ($class,$caller) = ($_[1],caller);
    die "Mal-formed package name '$class'" unless $class =~ /^(?:\w|(?<!^)(?<!:)::(?!\z))+\z/;
    die "Namespace already exists" if (keys %{"$class\::"});
    *{"$class\::"} = \*{"$caller\::"};
    ($class .= ".pm") =~ s!::!/!g;
    ($caller .= ".pm") =~ s!::!/!g;
    $INC{$class} = exists $INC{$caller} ? $INC{$caller}:$0; 
 
    1;
}

1;

##</code><code>##

# here we are in Utils.pm

package main;

use as "Utils";

package Utils;

...