haskell - 从模块中重新导出函数

Question

我有一个这样的模块

module A where

import qualified Data.Maybe as Maybe

fromMaybe = Maybe.fromMaybe

是否可以仅从 Data.Maybe 重新导出某些功能？ ?我不想重新导出整个 Data.Maybe模块，但只是一些功能，如 fromMaybe .

Answer 1

是的，您可以有选择地重新导出函数:

module A (
  module A,
  Maybe.fromMaybe ) where 

import qualified Data.Maybe as Maybe

() 中的文章在模块定义定义您要导出的内容之后。这里我们说“导出所有 module A 以及函数 Maybe.fromMaybe 。”