package parent; use strict; use vars qw($VERSION); $VERSION = '0.236'; sub import { my $class = shift; my $inheritor = caller(0); if ( @_ and $_[0] eq '-norequire' ) { shift @_; } else { for ( my @filename = @_ ) { s{::|'}{/}g; require "$_.pm"; # dies if the file is not found } } { no strict 'refs'; push @{"$inheritor\::ISA"}, @_; # dies if a loop is detected }; }; 1; __END__