Formal grammars

Some tools to run algorithms on context-free grammars (CFG). Requires Python 3.7.

Usage

• git clone https://github.com/magnickolas/formal_grammars && cd formal_grammars
• python3 -m venv venv && . venv/bin/activate && pip install -r requirements.txt
• Put the CFG's rules inside grammar file, see an example there
• Use one of the following algorithms:
  • LL(1)-parser builder: print LL(1)-parser table

    python -m formal_grammars ll1
    

  • LR(1)-parser builder: print LR(1)-parser table

    python -m formal_grammars lr1
    

  • Cocke — Younger — Kasami table builder: checks if a word is accepted by the grammar (the implementation accepts an arbitrary CFG).

    python -m formal_grammars cyk <word:str>
    

  • Grammar words generator: generate words from the grammar in alphabetical order (uses CYK algorithm)

    python -m formal_grammars gen [-n <num:int, 20>]
    

For educational purposes only.