Experimental Physics and
Industrial Control System

Benjamin Franksen <[email protected]> · Fri, 3 Oct 2008 00:15:44 +0200

On Donnerstag, 2. Oktober 2008, Andrew Johnson wrote:
> Other warnings are from 
> code generated by flex and/or antelope, which we didn't write and are not
> programs I want to look inside if I don't have to.

I recently discovered a nice alternative to yacc/bison/antelope which is 
called Lemon, see http://www.hwaci.com/sw/lemon/ . It is used e.g. in 
sqlite to parse SQL. Here are the highlights (from the home page):

 * Lemon using a different grammar syntax which is less prone to
   programming errors.
 * The parser generated by Lemon is both re-entrant and thread-safe.
 * Lemon includes the concept of a non-terminal destructor, which
   makes it much easier to write a parser that does not leak memory.

IIRC, EPICS has made changes to (its own copy of) antelope in order to 
address points 2 and 3 above.

I should add that lemon creates code with a nice and clear procedure based 
API, and that it does not contain a lexer generator (however, there is re2c 
for that).

Cheers
Ben

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System