Distribution/Compat/Environment.hs

    {-# LANGUAGE CPP #-}
    {-# OPTIONS_HADDOCK hide #-}

    module Distribution.Compat.Environment (getEnvironment)
           where

    import qualified System.Environment as System

    #ifdef mingw32_HOST_OS
    import qualified Data.Char as Char (toUpper)
    #endif

    getEnvironment :: IO [(String, String)]
    #ifdef mingw32_HOST_OS
    -- On Windows, the names of environment variables are case-insensitive, but are
    -- often given in mixed-case (e.g. "PATH" is "Path"), so we have to normalise
    -- them.
    getEnvironment = fmap upcaseVars System.getEnvironment
      where
        upcaseVars = map upcaseVar
        upcaseVar (var, val) = (map Char.toUpper var, val)
    #else
    getEnvironment = System.getEnvironment
    #endif