Haskell Even Function?

haskell

Solution

The code works fine if you change `even n` to `even ns`:

squareEvens n = [ns * ns | ns <- n, even ns]

But note that the convention is to use the plural to name the list and the singular to name an element from that list. So swap `n` and `ns` to follow idiomatic Haskell usage:

squareEvens ns = [n * n | n <- ns, even n]

Problem

This is probably a fairly obvious question, but I just can't figure it out. I am trying to write a function that squares the even numbers in a list. When I try to run it, I am getting an error about my use of the even function. How can I fix this? ``` module SquareEvens where squareEvens :: [Integer] -> [Integer] squareEvens n = [ns * ns | ns <- n, even n] ```

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