{
    use lib "..";
    use strict;  # "../strict.pm" loaded instead of the real one
}

##</code><code>##

#!/usr/bin/perl -W

BEGIN { push @INC, ".." }

use strict;              # "../strict.pm" untouched

eval "use Foo::Bar 5.01 qw| raz baz taz |";  # try loading v5.01
if ($@) {                # if loading v5.01 failed
  warn "@_";             # fallback to using standard (v5.00)
  use Foo::Bar qw| baz |; # raz and taz arent valid tags here
}
...