John's optimizations

src/Sapl/FastString.icl

@@ -6,48 +6,40 @@ skipChars :: !String !Int (Char -> Bool) -> Int
 skipChars line start f
 	| start == size line
 		= size line
-	| f line.[start]
+	#! c = line.[start]
+	| f c
 		= skipChars line (start + 1) f 
 		= start
 
 startsWith :: !String !String -> Bool
 startsWith start str
-	| (size str) >= (size start)
-		= startsWith_ ((size start)-1)
-		= False
+	= size str >= size start && startsWith_ ((size start)-1)
 where
 	startsWith_ -1 = True
 	startsWith_ starti
-		= case start.[starti] == str.[starti] of
-				True = startsWith_ (starti-1)
-					 = False
+		= start.[starti] == str.[starti] && startsWith_ (starti-1)
 					 
 endsWith :: !String !String -> Bool
 endsWith end str
-	| (size str) >= (size end)
-		= endsWith_ ((size end)-1) ((size str)-1)
-		= False
+	= size str >= size end && endsWith_ (size end-1) (size str-1)
 where
 	endsWith_ -1 _ = True
 	endsWith_ endi stri 
-		= case end.[endi] == str.[stri] of
-				True = endsWith_ (endi-1) (stri-1)
-					 = False
+		= end.[endi] == str.[stri] && endsWith_ (endi-1) (stri-1)
 
 charIndex :: !String !Int !Char -> (!Bool,!Int)
 charIndex s i char
-	| i == (size s)
+	| i < size s
+		| s.[i] == char
+			= (True,i)
+			= charIndex s (i+1) char
+	| i == size s
 		= (False,size s)
-		
-		| i < (size s)
-			| s.[i] == char
-				= (True,i)
-				= charIndex s (i+1) char
-			= abort "CharIndex: index out of range"
+		= abort "CharIndex: index out of range"
 					
 charIndexBackwards :: !String !Int !Char -> (!Bool,!Int)
 charIndexBackwards s i char
-	| i == (-1)
+	| i == -1
 		= (False,size s)
 		
 		| s.[i] == char
@@ -56,19 +48,22 @@ charIndexBackwards s i char
 			
 matchAt :: !String !String !Int -> Bool
 matchAt s1 s2 p 
-	| ((size s1) + p) > (size s2) 
-				= False
-				= eqS ((size s1) - 1)
-where
-	eqS 0 = s1.[0] == s2.[p + 0]
-	eqS i = s1.[i] == s2.[p + i] && eqS (i - 1) 
+	= size s1 + p <= size s2 && match_at 0 p
+	where
+		match_at :: !Int !Int -> Bool
+		match_at i1 i2
+			| i1<size s1
+				= s1.[i1]==s2.[i2] && match_at (i1+1) (i2+1)
+				= True
 
 countCharBackwards :: !Char !String -> Int
 countCharBackwards chr str 
-	= count ((size str)-1)
+	= count ((size str)-1) 0 str
 where
-	count -1
-		= 0
-	count pos | str.[pos] == chr
-		= 1 + count (pos-1)
-		= 0
+	count :: !Int !Int !String -> Int
+	count -1 n_chars str
+		= n_chars
+	count pos n_chars str
+		| str.[pos] == chr
+			= count (pos-1) (n_chars+1) str
+			= n_chars