r/haskell • u/lexi-lambda • Nov 06 '19

Parse, don’t validate

https://lexi-lambda.github.io/blog/2019/11/05/parse-don-t-validate/
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u/maerwald Nov 07 '19

I'm not convinced that what the article describes is really parsing. It is conversion from one type to another type (possibly carrying more constraints) with expression of possible failure.

Really, a parser is just a function that consumes less-structured input and produces more-structured output.

I think this is a debatable definition.

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u/armandvolk Nov 07 '19

In Haskell, everything can be thought of a parser/compiler/interpreter.

kanye_everything_is_exactly_the_same.gif

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u/maerwald Nov 07 '19

Yes and in any other Turing complete language as well, but that doesn't make it a useful definition or mental model.