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A comment on Swift and the Legacy of Functional Programming. Parent comment

Re:Swift and the Legacy of Functional Programming by jfoutz on Monday November 21, 2016 @05:40PM (#13009916)
> You're just duplicating the validation logic (or worse, the "objects creation" assumes it's given valid names and does no checks)

I think the right way to do it is with a fold.

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Re:Swift and the Legacy of Functional Programming by masklinn on Tuesday November 22, 2016 @03:52AM (#13012698)
In Haskell you'd use `mapMaybe :: (a -> Maybe b) -> [a] -> [b]`[0], it's a combined map+filter+map specialised for Maybe (option types). Rust has Iterator::filter_map[1] which does more or less the same thing.

[0] http://hackage.haskell.org/package/base-4.9.0.0/docs/Data-Ma...

[1] https://doc.rust-lang.org/std/iter/trait.Iterator.html#metho...

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