A (yet) fictionnal ruby gem, that allow to run pyhon code

Parsing python 🚧

In ruby

• Treetop - the PEG parser
• racc - an LALR(1) parser generator.

In Python

• Lark / doc / online ide - a parsing toolkit for Python support Earley and LARL.
  • Python 3 grammar for Lark - uses the Earley parser not LALR, because python’s grammar has context-sensitive features
  • transformed versions of the grammar can be parsed with LALR(1)
  • using a PEG/packrat parser won’t have these limitation and should allow for the same.

Parsing Indentation

Python3 lark indentation support

Pure PEG cannot parse indentation. But some PEG parser can.

• PEG for Python style indentation
  • Parse indentation level with PEG.js
  • You can do this in Treetop by using semantic predicates.