package Foo:Foo;
use strict;

# ... a buncha stuff here

sub declare_text {  # noop if this isn't under MacPerl
  if($MacPerl::Version) {
    foreach my $item (@_) {
       &MacPerl::SetFileInfo('R*ch', 'TEXT', $item);
    }
  }
  return;
}

#... more stuff
1;
__END__