Get a sublist in Haskell

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死守一世寂寞
死守一世寂寞 2021-02-18 20:50

Probably an easy one, but I\'ve looked through the docs and googled for examples and I\'m still not sure of the answer.

If I have a list like this:

[1,2,         


        
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  •  借酒劲吻你
    2021-02-18 21:20

    First of all, that's not an array, it's a list. I'm not being (merely) pedantic, as arrays are much more problematic in Haskell than lists.

    That said, one common way is to use take and drop together:

    Prelude> drop 4 . take 9 $ [1,2,3,4,5,6,7,8,9,0]
    [5,6,7,8,9]
    Prelude> take (9-4) . drop 4 $ [1,2,3,4,5,6,7,8,9,0]
    [5,6,7,8,9]
    

    The latter is a bit more efficient.

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