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chiroptical/FindJust.hs

Last active May 8, 2020 20:17
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Find first `Just` embedded in `[m (Maybe a)]`
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FindJust.hs
{-# LANGUAGE LambdaCase #-}
module FindJust ( findJust ) where
import Control.Monad ( foldM )
findJust :: Monad m => [m (Maybe a)] -> m (Maybe a)
findJust = foldM (\acc x -> maybe x (pure . Just) acc) Nothing
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