[Haskell-cafe] Wondering if this could be done.

[Magicloud Magiclouds]

Hi,
  For example, I have a data A defined. Then I want to add (+) and (-)
operators to it, as a sugar (compared to addA/minusA). But * or other
stuff defined in class Num is meanless to A. So I just do:
(+) :: A -> A -> A
(+) a b =
  A (elem1 a + elem1 b) (elem2 a + elem2 b) -- I got errors here, for
the (+) is ambiguous.

  So, just wondering, does this way work in Haskell?
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