Fixed miscellaneous minor errors

2 files changed, 31 insertions, 29 deletions

diff --git a/Thue/Interpreter.hs b/Thue/Interpreter.hs
index 8555bab..6022038 100644
--- a/Thue/Interpreter.hs
+++ b/Thue/Interpreter.hs
@@ -1,9 +1,11 @@
 module Interpreter (
-	thue
-	) where
+    thue
+    ) where
 
 
 import System.Random
+import Data.Maybe
+import Data.List
 import Parser
 
 
@@ -11,56 +13,56 @@ import Parser
 
 thue :: ThueProgram -> ThueState
 thue program =
-	let rules = thueRules program
-	    state = thueInitialState program
-	    gen = mkStdGen 4 --chosen by fair dice roll, guaranteed to be random
+    let rules = thueRules program
+        state = thueInitialState program
+        gen = mkStdGen 4 --chosen by fair dice roll, guaranteed to be random
 
     in interpret state rules gen
 
 
 
-interpret :: ThueState -> [ThueRule] -> RandomGen -> ThueState
+interpret :: ThueState -> [ThueRule] -> StdGen -> ThueState
 interpret state rules gen =
-	let possibleRules = rules `applicableTo` state
-	    ruleToApply = possibleRules !! num
+    let possibleRules = rules `applicableTo` state
+        ruleToApply = possibleRules !! num
 
         (num, gen') = nextInRange 0 (length possibleRules - 1) gen
 
-	    (before, after) = fromJust (extractInfix (original ruleToApply) state)
-	    state' = before ++ (replacement ruleToApply) ++ after
+        (before, after) = fromJust (extractInfix (original ruleToApply) state)
+        state' = before ++ (replacement ruleToApply) ++ after
 
-	in if (possibleRules == []) then state else interpret state' rules gen'
+    in if (possibleRules == []) then state else interpret state' rules gen'
 
 
 
-extractInfix :: [a] -> [a] -> Maybe ([a], [a])
+extractInfix :: Eq a => [a] -> [a] -> Maybe ([a], [a])
 extractInfix subList list =
-	let f = (\pre cur -> case (stripPrefix subList cur) of
-		                    Nothing -> f (head cur):pre (tail cur)
-		                    Just x -> (reverse pre, x)
+    let f = (\pre cur -> case (stripPrefix subList cur) of
+                            Nothing -> f ((head cur):pre) (tail cur)
+                            Just x -> (reverse pre, x))
 
-	in if (subList `isInfixOf` list) then Just f [] list else Nothing
+    in if (subList `isInfixOf` list) then Just (f [] list) else Nothing
 
 
 
-nextInRange :: Integer -> Integer -> RandomGen -> (Integer,RandomGen)
+nextInRange :: Int -> Int -> StdGen -> (Int, StdGen)
 nextInRange low high random =
-	let (genLow, genHigh) = genRange random
-	    (rawNext, random') = next random
+    let (genLow, genHigh) = genRange random
+        (rawNext, random') = next random
 
-	    next = (\n -> let irawNext = fromIntegral rawNext
-	    	              igenLow = fromIntegral genLow
-	    	              igenHigh = fromIntegral genHigh
-	    	              ilow = fromIntegral low
-	    	              ihigh = fromIntegral high
-	    	              n' = ((irawNext - igenLow) / (igenHigh - igenLow)) * (ihigh - ilow) + ilow
-	    	          in round n'
+        irawNext = fromIntegral rawNext
+        igenLow = fromIntegral genLow
+        igenHigh = fromIntegral genHigh
+        ilow = fromIntegral low
+        ihigh = fromIntegral high
 
-	in (next, random')
+        n' = ((irawNext - igenLow) / (igenHigh - igenLow)) * (ihigh - ilow) + ilow
+
+    in (round n', random')
 
 
 
 applicableTo :: [ThueRule] -> ThueState -> [ThueRule]
 applicableTo ruleList state =
-	filter (\r -> (original r) `isInfixOf` state) ruleList
+    filter (\r -> (original r) `isInfixOf` state) ruleList
 
diff --git a/Thue/Parser.hs b/Thue/Parser.hs
index 3073014..1eb7943 100644
--- a/Thue/Parser.hs
+++ b/Thue/Parser.hs
@@ -17,7 +17,7 @@ data ThueProgram = ThueProgram { thueRules :: [ThueRule]
 
 data ThueRule = ThueRule { original :: ThueState
                          , replacement :: ThueState }
-    deriving (Show)
+    deriving (Show, Eq)
 
 
 type ThueState = String