Well, yes, I'm naughty. I've implemented a parameterized evaluator, using Unicode codepoint U+2282 as a parameter.

But the DRL parser refuses to accept this (as part of square_chunk_data):
Line 60:59 no viable alternative at input ''
which indicates that the character isn't recognized at all.

I think this happens because, outside of strings, codepoints beyond U+007F aren't accepted anywhere except
those explicitly specified as IdentifierStart and IdentifierPart. Perhaps square_chunk_data after an operator
identifier could be made to behave more like a string.

Admittedly, this is esoteric, but it sure does look dazzling ;-)

Cheers
-W