It is a cardinal mistake in any language to extrapolate behavior from a few examples without having Read The Fine Manual. The docs will tell you what the special cases are. And even if you don't remember the special cases, you'll know that they are there, and then should know to re-read the docs when your code isn't behaving as expected.

This is true with Perl; it is true with Java; and it is likely true with any other language you can name. Languages have special cases. Powerful languages like Perl are likely to have more special cases. It's frustrating to run into them, and it's embarrassing when people point you back to the documentation (it's embarrassing to me, at least), but that's just how it is.

Read (and re-read) perlre before you try to drop your problems at dot star's door.