Changeset 12104 for src/Pugs/Val

Timestamp:

08/11/06 09:11:00 (2 years ago)

Author:

gaal

Message:

* PureNum? encapsulates both floating-point and fractional values
* add Val.Sig (not compiled at the moment, waiting on circularity saw)

Location:

src/Pugs/Val

Files:

• Num.hs (modified) (1 diff)
• Sig.hs (added)

src/Pugs/Val/Num.hs

@@ -4 +4 @@
 import qualified Data.ByteString.Char8 as Char8
 
-instance ((:>:) PureNum) Double where cast = MkNum
-instance ((:<:) PureNum) Double where castBack (MkNum i) = i
+instance ((:>:) PureNum) Double where cast = NDouble
+instance ((:<:) PureNum) Double where
+    castBack (NDouble   x) = x
+    castBack (NRational x) = fromRational x
 
-instance ((:>:) PureNum) Int where cast = MkNum . fromIntegral
+instance ((:>:) PureNum) Rational where cast = NRational
+instance ((:<:) PureNum) Rational where
+    castBack (NDouble   x) = toRational x
+    castBack (NRational x) = x
 
-newtype PureNum = MkNum Double
-    deriving (Typeable, Show, Eq, Ord, Data, (:>:) Double, (:<:) Double)
+instance ((:>:) PureNum) Int where cast = NRational . fromIntegral
+
+data PureNum
+    = NDouble   !Double              -- change to "!NativeDouble"
+    | NRational !Rational
+    deriving (Typeable, Show, Eq, Ord, Data)
 
 {- regretfully, I couldn't find a way to put this here w/o circularity.