Fix all orphan instances.

[spline3.git] / src / Cardinal.hs

diff --git a/src/Cardinal.hs b/src/Cardinal.hs
index 9032fbdfd4312907474c9b0e4da32928a8add648..3bff38f206c5983cb29ac9f80ef99275f6a88e4c 100644 (file)
--- a/src/Cardinal.hs
+++ b/src/Cardinal.hs
@@ -6,7 +6,9 @@
 module Cardinal
 where
 
+import Control.Monad (liftM, liftM2)
 import Prelude hiding (LT)
+import Test.QuickCheck (Arbitrary(..), oneof)
 
 data Cardinal = F   -- ^ Front
               | B   -- ^ Back
@@ -68,6 +70,46 @@ instance Fractional Cardinal where
     fromRational x = Scalar (fromRational x)
 
 
+
+instance Arbitrary Cardinal where
+    arbitrary = oneof [f,b,l,r,d,t,fl,fr,fd,ft,bl,br,bd,bt,ld,lt,
+                       rd,rt,fld,flt,frd,frt,bld,blt,brd,brt,i,
+                       scalar,csum,cdiff,cprod,cquot]
+        where
+          f = return F
+          b = return B
+          l = return L
+          r = return R
+          d = return D
+          t = return T
+          fl = return FL
+          fr = return FR
+          fd = return FD
+          ft = return FT
+          bl = return BL
+          br = return BR
+          bd = return BD
+          bt = return BT
+          ld = return LD
+          lt = return LT
+          rd = return RD
+          rt = return RT
+          fld = return FLD
+          flt = return FLT
+          frd = return FRD
+          frt = return FRT
+          bld = return BLD
+          blt = return BLT
+          brd = return BRD
+          brt = return BRT
+          i = return I
+          scalar = liftM Scalar arbitrary
+          csum = liftM2 Sum arbitrary arbitrary
+          cdiff = liftM2 Difference arbitrary arbitrary
+          cprod = liftM2 Product arbitrary arbitrary
+          cquot = liftM2 Quotient arbitrary arbitrary
+
+
 -- | Rotate a cardinal direction counter-clockwise about the x-axis.
 ccwx :: Cardinal -> Cardinal
 ccwx F = F