[Haskell-cafe] Not in scope: type constructor or class `Map'

Eric Stansifer eric.stansifer+haskell at gmail.com
Thu Dec 30 17:15:06 CET 2010


Because Data.Map is imported qualified, any symbols in it (including
Map) needs to be qualified:

type Bindings = Map.Map String Int


A standard idiom is to do import like so:

import qualified Data.Map as Map
import Map (Map)

so that the Map symbol itself does not need qualification.

Eric



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