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A comment on LALRPOP, an LR(1) parser generator for Rust. Parent comment

Re:LALRPOP, an LR(1) parser generator for Rust by mjburgess on Monday January 25, 2021 @11:03AM (#25904722)
It's harder to express complex grammars in combinator form.

Combinators excel best for relatively simply regular languages (eg., json, html, etc.).

Languages with lots of "modality" in parsing, ie., context switching, are easier to express in generator-form (eg., antlr).

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Re:LALRPOP, an LR(1) parser generator for Rust by royjacobs on Monday January 25, 2021 @01:16PM (#25906613)
Wouldn't the mode be encoded in the type system via the tokens your parser is generating? I mean, every mode would be a different enum containing all the tokens that are valid in that mode?
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Re:LALRPOP, an LR(1) parser generator for Rust by mjburgess on Tuesday January 26, 2021 @02:03AM (#25913303)
Sure, I imagine it's possible to express any parser-generator grammar in combinator form. It's just a question of how easy it is to do by hand, and how efficient the parsing process would be.
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