[wyufro]

In my experience the hardest part of using parser generators is to have them create understandable errors.

Also it's questionable that they add very much. Parsing text isn't all that difficult. The hard part is to get the tree structure of the AST right.

All in all the parsing is a quite small part of a compiler. I've converted from a parser generated to manual code in two different projects and they actually ended up with less lines of code after the conversion, if just barely.