More about string adding

For the ignorant

I hoped that the behavior mentioned in my previous post could be the way to get around wonky Unicode reading in mkm's binary file functions until pre7 is finally released.
But arithmetic operations on strings returns a completely different type of string incompatible with ordinary strings. So ("A" + "!" - "A") == ("A" + "!" - "A") returns true, but ("A" + "!" - "A") == "!" gives an error.
So mkm can write a great danmaku engine, but he can't get typing quite right.