MethodExpr or ##func() syntax documentation

[chwmilcon]

I found syntax within the grammar.rustpeg that appears to be means of calling an external parsing function within the rust-peg grammar. rule PAREN_GROUP() -> Group = ##group(Delimiter::Parenthesis)

This is a great feature, but I'm not finding documentation for it for rust-peg. Am I missing it?

[kevinmehall]

It's a hack that's there because I needed it for the PEG meta-grammar, but I never documented it, because I'd planned to replace it with something more flexible not tied to the input type: #284

Not going to break it without a breaking semver bump, so feel free to use it though.

[chwmilcon]

Thank you for clarifying. It feels similar to the @extern(...) from peginator