[project @ 1999-05-18 15:03:54 by simonpj]

[ghc-hetmet.git] / ghc / compiler / utils / Maybes.lhs

diff --git a/ghc/compiler/utils/Maybes.lhs b/ghc/compiler/utils/Maybes.lhs
index 98efdb7..2f6118f 100644 (file)
--- a/ghc/compiler/utils/Maybes.lhs
+++ b/ghc/compiler/utils/Maybes.lhs
@@ -8,6 +8,7 @@ module Maybes (
 --     Maybe(..), -- no, it's in 1.3
        MaybeErr(..),
 
+       orElse, 
        mapMaybe,
        allMaybes,
        firstJust,
@@ -29,6 +30,9 @@ module Maybes (
 #include "HsVersions.h"
 
 import Maybe( catMaybes, mapMaybe )
+
+
+infixr 4 `orElse`
 \end{code}
 
 
@@ -96,6 +100,10 @@ returnMaybe = Just
 
 failMaybe :: Maybe a
 failMaybe = Nothing
+
+orElse :: Maybe a -> a -> a
+(Just x) `orElse` y = x
+Nothing  `orElse` y = y
 \end{code}
 
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