小编Pot*_*mpo的帖子

似乎提高Complex Int权力违反了某些合同.我错了吗？

以下最小例子

compl :: Complex Int -> Maybe (Complex Int)
compl d = (d^) <$> Just 3

并且错误消息:

No instance for (RealFloat Int) arising from an operator section
      In the first argument of ‘(<$>)’, namely ‘(d ^)’
      In the expression: (d ^) <$> Just 3
      In an equation for ‘compl’: compl d = (d ^) <$> Just 3

有没有办法解决？允许这种类型是浮点数在我的程序中没有任何意义.