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Why is strong emphasis used when passing a mod function to display?

I am studying Haskell, but I did not find the answer to this question.

Why is serious emphasis used to pass the mod function to display, as in the example? I have seen other cases with other functions where this is not needed.

 map (`mod` 3) [1..6] -- result is [1,2,0,1,2,0]

If I pass without a serious accent, the result will be completely different.

 map (mod 3) [1..6] -- result is [0,1,0,3,3,3]
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2 answers

The emphasis "makes the function behave like an operator." For instance:

 mod ab == a `mod` b

So

 (mod 3) == mod 3 ?

and

 (`mod` 3) == mod ? 3
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If you want to clearly understand what you are thinking about (I always do mine, since I'm still in the learning phase), you can always use an anonymous function (sometimes I call a lambda expression, but I'm not sure)

 > map (\x -> x `mod` 3) [1..10] [1,2,0,1,2,0,1,2,0,1] > map (\x -> 3 `mod` x) [1..10] [0,1,0,3,3,3,3,3,3,3] > map (\x -> mod x 3) [1..10] [1,2,0,1,2,0,1,2,0,1] > map (\x -> mod 3 x) [1..10] [0,1,0,3,3,3,3,3,3,3]
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