Oh, but C parsers often do a trick like extending the lexer when typedefs are encountered. Typedefs part of the challange of parsing C correctly. And the lexer should definitely know about C's keywords. That's what the lexer is for.

        -- Lennart

On Apr 15, 2007, at 07:46 , Stefan O'Rear wrote:

On Sun, Apr 15, 2007 at 07:42:02AM +0100, Lennart Augustsson wrote:
But the qualifiers aren't arbitrary names, are they?

Yes they are.  I don't have knowledge of typedefs used :)

Nice try though, I toyed with that idea for a long while.  Ultimately
I decided that it would complicate the lexer too much to add knowledge
of C's keywords.  Then I thought of the typedef problem.

On Apr 15, 2007, at 04:52 , Stefan O'Rear wrote:

I'm writing a code generator for C, and I'm trying to parse a C-like
input language using LL(1) (parsec specifically).  The syntax of
declarators is giving me trouble: (simplified)

declaration = qualifiers >> (declarator `sepBy1` char ',')
qualifiers = many1 name
declarator = name

now if we have "<name> <name>", they are both parsed by the greedy
many1 in qualifiers! I can make this work with some ugly rearranging:

declaration = fdeclarator >> many (char ',' >> declarator)
fdeclarator = name >> many1 name
declarator = name

is there a more elegant way?

Stefan

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