Fix a bug in eqPatType

One of the conditions we were checking was
    t2 `eqPatLType` t2
rather than
    t1 `eqPatLType` t2

diff --git a/compiler/typecheck/TcClassDcl.lhs b/compiler/typecheck/TcClassDcl.lhs
index 49d2088..dc3f446 100644 (file)
--- a/compiler/typecheck/TcClassDcl.lhs
+++ b/compiler/typecheck/TcClassDcl.lhs
@@ -676,8 +676,8 @@ eqPatType :: HsType Name -> HsType Name -> Bool
 -- A very simple equality function, only for 
 -- type patterns in generic function definitions.
 eqPatType (HsTyVar v1)       (HsTyVar v2)      = v1==v2
-eqPatType (HsAppTy s1 t1)    (HsAppTy s2 t2)   = s1 `eqPatLType` s2 && t2 `eqPatLType` t2
-eqPatType (HsOpTy s1 op1 t1) (HsOpTy s2 op2 t2) = s1 `eqPatLType` s2 && t2 `eqPatLType` t2 && unLoc op1 == unLoc op2
+eqPatType (HsAppTy s1 t1)    (HsAppTy s2 t2)   = s1 `eqPatLType` s2 && t1 `eqPatLType` t2
+eqPatType (HsOpTy s1 op1 t1) (HsOpTy s2 op2 t2) = s1 `eqPatLType` s2 && t1 `eqPatLType` t2 && unLoc op1 == unLoc op2
 eqPatType (HsNumTy n1)      (HsNumTy n2)       = n1 == n2
 eqPatType (HsParTy t1)      t2                 = unLoc t1 `eqPatType` t2
 eqPatType t1                (HsParTy t2)       = t1 `eqPatType` unLoc t2