Fix imports for issue #19

.ghci

@@ -4,5 +4,6 @@
 :set -Wall
 :set -fno-warn-unused-binds
 :set -fno-warn-unused-do-bind
+:set -fno-warn-unused-imports
 :set -fno-warn-type-defaults
 

course.cabal

@@ -35,6 +35,7 @@ library
   ghc-options:      -Wall
                     -fno-warn-unused-binds
                     -fno-warn-unused-do-bind
+                    -fno-warn-unused-imports
                     -fno-warn-type-defaults
 
   hs-source-dirs:   src

src/Algorithm/Cheque.hs

@@ -15,6 +15,8 @@ data structures that may assist you in deriving the result. It is not compulsory
 
 module Algorithm.Cheque where
 
+import Data.Maybe
+import Data.Char
 import Data.List
 import Control.Applicative
 

src/Algorithm/FastAnagrams.hs

@@ -2,6 +2,8 @@ module Algorithm.FastAnagrams where
 
 import Data.Char
 import Data.Function
+import qualified Data.Set as S
+import Data.List
 
 -- Return all anagrams of the given string
 -- that appear in the given dictionary file.

src/IO/Interactive.hs

@@ -5,6 +5,7 @@ module IO.Interactive where
 import Core
 import Monad.Functor
 import Monad.Monad
+import Data.Char
 import Structure.List
 import Intro.Optional
 

src/Monad/State.hs

@@ -4,11 +4,14 @@
 module Monad.State where
 
 import Core
+import qualified Prelude as P
+import Data.Char
 import Intro.Optional
 import Structure.List
 import Monad.Functor
 import Monad.Monad
 import qualified Data.Foldable as F
+import qualified Data.Set as S
 
 -- $setup
 -- >>> import Test.QuickCheck.Function

src/Monad/StateT.hs

@@ -8,6 +8,8 @@ import Intro.Optional
 import Structure.List
 import Monad.Functor
 import Monad.Monad
+import Monad.State
+import qualified Data.Set as S
 
 -- | A `StateT` is a function from a state value `s` to a functor f of (a produced value `a`, and a resulting state `s`).
 newtype StateT s f a =

src/Parser/JsonParser.hs

@@ -1,7 +1,10 @@
 module Parser.JsonParser where
 
 import Parser.Parser
+import Parser.MoreParser
+import Numeric
 import Parser.JsonValue
+import Control.Applicative
 
 -- Exercise 1
 -- | Parse a JSON string. Handle double-quotes, control characters, hexadecimal characters.

src/Parser/MoreParser.hs

@@ -1,6 +1,9 @@
 module Parser.MoreParser where
 
 import Parser.Parser
+import Data.Char
+import Numeric
+import Control.Monad
 
 -- $setup
 -- >>> import Parser.Parser(isErrorResult, character, lower, is)

src/Parser/Parser.hs

@@ -1,5 +1,6 @@
 module Parser.Parser where
 
+import Data.Char
 import Control.Applicative
 import Parser.Person
 

src/Structure/BKTree.hs

@@ -17,6 +17,7 @@ import Structure.MetricSpace
 import Data.Map(Map)
 import qualified Data.Map as M
 import Data.Foldable
+import qualified Data.Foldable as F
 import Data.Monoid
 
 data BKTree a =