Amateurs use parser-generators. Professionals write recursive-descent parsers. Real men code finite state machines by hand: http://galileo.phys.virginia.edu/c

Amateurs use parser-generators. Professionals write recursive-descent parsers. Real men code finite state machines by hand: http://galileo.phys.virginia.edu/classes/551.jvn.fall01/fsm.html http://galileo.phys.virginia.edu/classes/551.jvn.fall01/fsm.... But seriously, the mystery and ignorance that continues to surround Yacc to this day needs to be fought. If you're using Yacc, you're doing it wrong. As far as parser-generators go, it is totally obsolete, and even when it wasn't, it was the wrong choice for almost all parsing problems. I learned this one day when someone recoded a Yacc-based parser I wrote in recursive-descent style, and it was less lines of code than my specification. If you need to write a really simple, or a really complicated, parser, recursive-descent is usually the way to go. You might try Henry Baker's META (http://home.pipeline.com/~hbaker1/Prag-Parse.html http://home.pipeline.com/~hbaker1/Prag-Parse.html) as a first alternative. If you really, really feel the need for a parser-generator, take a look at parsing expressions grammars/packrat parsers: http://pdos.csail.mit.edu/~baford/packrat/ http://pdos.csail.mit.edu/~baford/packrat/ But the real lesson here is to design your syntax to be easy to parse and manipulate in the first place. C's grammar is the clearest testament to how little thought Dennis Ritchie put into the design of C.