[pypy-dev] Notes on compiler package

logistix logistix at zworg.com
Thu Jan 23 05:44:55 CET 2003

> > 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 ;-)

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