Haskell reverse function application operator not working

Question

I'm playing around with Haskell, but I can't figure out why the reverse function application operator (&) is not working.

For example in ghci I get:

Prelude> "hello" & length

<interactive>:1:9: error:
    Variable not in scope: (&) :: [Char] -> ([a0] -> Int) -> t

When I expect it to return 5

Why is it not working?

It is in the Data.Function module, and not reimported in the Prelude, so you need to import it yourself. — willeM_ Van Onsem
– willeM_ Van Onsem, Commented Mar 20, 2018 at 20:56

Koterpillar · Accepted Answer · 2018-03-20 20:55:52Z

8

Looks like it's not in scope. Asking Hoogle tells me that you need to import it from, for example, Data.Function:

Prelude> import Data.Function
Prelude Data.Function> "hello" & length
5

answered Mar 20, 2018 at 20:55

Koterpillar

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