aha, i tried using 'let' on the assumption that he was just being brief, but I put a 'let' in front of each of the pattern-matching function signatures, which didn't work. Thanks.
edit: I take your last comment as "when using the REPL, it is easier not to use the REPL." :D
edit: I take your last comment as "when using the REPL, it is easier not to use the REPL." :D