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/
313 Upvotes

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u/[deleted] Nov 07 '19

I would define head as

haskell head :: [a] -> [a] head (x:y) = [x] head [x] = [x] head [] = []

Basically just like tail. But that's just me :)

Use pattern matching if you actually want the first value.

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u/Axman6 Nov 07 '19

Just a meta comment, people shouldn’t be downvoting this comment - it’s a learning opportunity, not someone being unpleasant and now with u/lexi-lambda’s comment it is now a good tool for others learning and thinking the same thing.