...

P.S. If anyone can point me to some sort of definition of what the "Extended" in ELL(1) stands for I'd appreciate it. Python grammar is not LL(1) as written.

Are you trying to use a parser generator?

ciao - chris

Nah, that's what I already wrote one in the above stuff. But I had to backtrack to get it to work on parts of the grammar like: varargslist: (fpdef ['=' test] ',')* ('*' NAME [',' '**' NAME] | '**' NAME) | fpdef ['=' test] (',' fpdef ['=' test])* [','] The backtracking wasn't a big deal, but it shouldn't be necessary in an LL(1) grammar. The source claims that the grammar is ELL(1). I was wondering if the ELL definition addressed my backtracking issues, so that I could confirm that my assumptions about where I throw my Syntax Errors were valid. To use XML terminology, my current assumptions are only well-formed ;-)