Re: [Haskell-beginners] Maybe?

Maybe a is a sum type. Show instance for sum types displays the constructor. For example, if we used another sum type: Either Int Int, then Left 23 /= Right 23 So we'd be interested to see the constructor to tell them apart. 23 wouldn't be sufficiently clear. On Wed, May 13, 2020 at 5:18 PM Velichko Lefterov < velichko.lefterov@gmail.com> wrote:

The function returns Maybe a.

On Wed, May 13, 2020 at 5:16 PM Alexander Chen wrote:

...

I expected

prelude> safeHead [23,1,4,2,4,2] 23

not Just 23

May 13, 2020 4:11:47 PM CEST Imants Cekusins wrote:

prelude> safeHead [23,1,4,2,4,2] Just 23

Looks good.

What did you expect to see?

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