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

Pedro Vasconcelos pbv at dcc.fc.up.pt
Thu Dec 30 17:17:19 CET 2010

On Thu, 30 Dec 2010 08:01:01 -0800 (PST)
michael rice <nowgate at yahoo.com> wrote:

> Not sure what's going on here. Doesn't like line 5, the type
> statement. And what's with the semicolons in that line and in
> function main?

> import Control.Monad.Reader
> import qualified Data.Map as Map
> import Data.Maybe
> type Bindings = Map String Int;
The right hand side should be "Map.Map String Int"; alternatively
add an unqualified import above for just the Map type:

> import Data.Map(Map)

The semicolon is optional---the layout rule will insert it if you leave
it out.


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