1 1.1 christos Berkeley Yacc (byacc) is a LALR(1) parser generator. Berkeley Yacc 2 1.1 christos has been made as compatible as possible with AT&T Yacc. Berkeley 3 1.1 christos Yacc can accept any input specification that conforms to the AT&T 4 1.1 christos Yacc documentation. 5 1.1 christos 6 1.1 christos Some programs depend on a byacc (instead of bison). 7