Separate ggenString so that it can be modified

Libraries/Gast/Gen.dcl

@@ -39,6 +39,18 @@ generic ggen a :: !GenState -> [a]
 
 genState :: GenState
 
+/**
+ * Generates an infinite list of random strings
+ *
+ * @param The maximum length of the strings
+ * @param The factor for which the probability decreases for longer strings
+ * @param Minimum character value
+ * @param Maximum character value
+ * @param A list of random numbers (e.g. aStream)
+ * @result An inifinite list of strings
+ */
+ggenString :: Int Real Int Int RandomStream -> [String]
+
 derive ggen Int, Bool, Real, Char, String
 derive ggen UNIT, PAIR, EITHER, CONS of gcd, OBJECT of gtd, FIELD of d, RECORD of grd
 derive ggen (,), (,,), (,,,), (,,,,), (,,,,,), (,,,,,,), (,,,,,,,)

Libraries/Gast/Gen.icl

@@ -186,19 +186,22 @@ where
         Nothing    -> f s
         Just limit -> take limit $ f s
 
-ggen{|String|} s = ["hello world!","Gast","": rndStrings aStream]
+ggenString :: Int Real Int Int RandomStream -> [String]
+ggenString maxlen factor minchar maxchar stream = rndStrings stream
 where
 	rndStrings [len:rnd] 
-		# len = toInt ((randIntToReal len) ^ 8.0 * (fromInt StrLen - 0.5))
+		# len = toInt ((randIntToReal len) ^ factor * (fromInt maxlen - 0.5))
 		# (chars,rnd)	= seqList (repeatn len genElem) rnd
 		  string		= {c \\ c<-chars}
 		= [string:rndStrings rnd]
 	where
 		genElem :: RandomStream -> .(Char, RandomStream)
-		genElem [r:rnd] = (toChar (32+((abs r) rem 94)), rnd)
+		genElem [r:rnd] = (toChar (minchar+((abs r) rem (maxchar-minchar))), rnd)
 
-randIntToReal :: Int -> Real
-randIntToReal x = (toReal x + if (x >= 0) 0.0 4294967296.0) / 4294967295.0
+		randIntToReal :: Int -> Real
+		randIntToReal x = (toReal x + if (x >= 0) 0.0 4294967296.0) / 4294967295.0
+
+ggen{|String|} s = ["hello world!","Gast","":ggenString StrLen 4.0 32 126 aStream]
 
 derive ggen (,), (,,), (,,,), (,,,,), (,,,,,), (,,,,,,), (,,,,,,,)
 derive ggen [], [!], [ !], [!!]