It could be done. At least one person I know is working on it. And
in fact Norbert Mikula's NXP uses, I believe, a lex/yacc-like-thingie
for Java. On the other hand, this is probably going to get you quite
large code size; also there will likely be problems handling encodings;
also these generators tend to make it hard to generate high-quality
error messages.
On the other hand, if you want a quick one-off in C, lex/yacc are proabably
a very reasonable strategy. -Tim