Data.Map的合格导入与Prelude冲突

Question

我想在我的代码中使用Prelude.map和Data.Map.map用于不同的目的,但合格的导入Data.Map似乎没有帮助:

Prelude> import Data.Map as M
Prelude M> map

<interactive>:3:1:
    Ambiguous occurrence ‘map’
    It could refer to either ‘M.map’
                             imported from ‘Data.Map’
                             (and originally defined in ‘containers-0.5.0.0:Data.Map.Base’)
                          or ‘Prelude.map’
                             imported from ‘Prelude’ (and originally defined in ‘GHC.Base’)

(我还拍了一个错误信息的截图,你可以在这里看到.)

我希望能够分别使用map和M.map; 我怎样才能做到这一点？

Answer 1

import Data.Map as M 从Data.Map导入限定和非限定的名称.

要仅导入限定名称,请使用:

import qualified Data.Map as M