shnewto / bnf

Parse BNF grammar definitions
MIT License
256 stars 22 forks source link

Nullable Rules? #78

Open shnewto opened 3 years ago

shnewto commented 3 years ago

Unsure if there's any desire for them at the moment, but while doing some reading, I realized we aren't explicitly supporting nullable productions, i.e. non-terminals that can represent zero terminals...

Further reading: https://en.wikipedia.org/wiki/Chomsky_normal_form https://web.stanford.edu/class/archive/cs/cs143/cs143.1156/handouts/parsing.pdf