Qualified Holes

Let us consider the following example code:

import qualified Data.Map as M

main :: IO ()
main = print (M._ (\k v acc -> k + v + acc) 0 myMap)

myMap :: Map Int Int
myMap = ...

This errors with Not in scope: M._. It would cool if GHC instead treated M._ as a hole but only gave suggestions from the module Data.Map. So, in this case, it would suggest things like Data.Map.foldrWithKey and Data.Map.foldlWithKey.

Trac metadata

Trac field	Value
Version	8.4.3
Type	FeatureRequest
TypeOfFailure	OtherFailure
Priority	low
Resolution	Unresolved
Component	Compiler
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