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Comment by rbonvall | Hacker News Reader

Python has pyparsing: https://pypi.org/project/pyparsing/

Maybe it's because non-FP languages typically don't support operator overloading, so you'd end up with verbose grammars like:

    new Literal("true").or(new Literal("false"))

and then you'll probably use a parser generator like ANTLR.

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Python is no Scala when it comes to operator overloading, but it has enough to make parser combinators work cleanly. funcparserlib [1] and Parsita [2] are two such libraries.

For example, this does what you probably expect in Parsita:

    real = reg(r'[+-]?\d+\.\d+(e[+-]?\d+)?') | 'nan' | 'inf' > float

(Full disclosure: I wrote Parsita.)

[1]: https://github.com/vlasovskikh/funcparserlib

[2]: https://github.com/drhagen/parsita

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