%empty directive doesn't execute semantic actions, /* empty */ does about jison

[GerHobbelt]

IIRC %empty is not supported by vanilla jison. jison-gho does support %empty though.

(You can check this by looking at the generated parser JS code: I bet jison treats %empty as a token and assigns it a token ID, which, of course, is never output by the lexer and thus resulting in a unreachable code section of your grammar.)

[fcruzel]

Didn't know there was a fork of Jison. Thank you. Since this repo it's no longer maintained I'm closing the issue.