[project @ 2002-02-11 08:20:38 by chak]

[ghc-hetmet.git] / ghc / compiler / deSugar / Match.lhs

diff --git a/ghc/compiler/deSugar/Match.lhs b/ghc/compiler/deSugar/Match.lhs
index 74be345..1f9fcda 100644 (file)
--- a/ghc/compiler/deSugar/Match.lhs
+++ b/ghc/compiler/deSugar/Match.lhs
@@ -24,7 +24,8 @@ import MatchCon               ( matchConFamily )
 import MatchLit                ( matchLiterals )
 import PrelInfo                ( pAT_ERROR_ID )
 import TcType          ( mkTyVarTys, Type, tcTyConAppArgs, tcEqType )
-import TysWiredIn      ( nilDataCon, consDataCon, mkTupleTy, mkListTy, tupleCon )
+import TysWiredIn      ( nilDataCon, consDataCon, mkTupleTy, mkListTy,
+                         tupleCon, parrFakeCon, mkPArrTy )
 import BasicTypes      ( Boxity(..) )
 import UniqSet
 import ErrUtils                ( addWarnLocHdrLine, dontAddErrLoc )
@@ -314,7 +315,8 @@ Replace the `as' pattern @x@@p@ with the pattern p and a binding @x = v@.
 \item
 Removing lazy (irrefutable) patterns (you don't want to know...).
 \item
-Converting explicit tuple- and list-pats into ordinary @ConPats@.
+Converting explicit tuple-, list-, and parallel-array-pats into ordinary
+@ConPats@. 
 \item
 Convert the literal pat "" to [].
 \end{itemize}
@@ -441,6 +443,15 @@ tidy1 v (ListPat ty pats) match_result
              (ConPat nilDataCon  list_ty [] [] [])
              pats
 
+-- introduce fake parallel array constructors to be able to handle parallel
+-- arrays with the existing machinery for constructor pattern
+--
+tidy1 v (PArrPat ty pats) match_result
+  = returnDs (parrConPat, match_result)
+  where
+    arity      = length pats
+    parrConPat = ConPat (parrFakeCon arity) (mkPArrTy ty) [] [] pats
+
 tidy1 v (TuplePat pats boxity) match_result
   = returnDs (tuple_ConPat, match_result)
   where