Integrate with cstree

[xamgore]

Hi! I like pest as I can just describe a grammar, while I like cstree for building a concrete syntax tree without tree node allocations. Is there a way to combine them?

[tomtau]

I guess it depends on what you mean by "combine" them.
I think SyntaxKind corresponds +- to the generated Rules enum in pest, so it should be possible to just process the outputted pairs into cstree (implement manually Syntax for the Rule enum and create the green tree by iterating over the pest pairs).
But I guess that may defeat the purpose a bit that one takes the pest concrete syntax tree and processes it into a different kind of tree... it'd be better if one could create it directly during parsing. So that's not possible at the moment, but it could be a thing in here: pest-parser/pest3#11 (comment)