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authorDavid Terei <davidterei@gmail.com>2011-07-20 11:09:03 -0700
committerDavid Terei <davidterei@gmail.com>2011-07-20 11:26:35 -0700
commit16514f272fb42af6e9c7674a9bd6c9dce369231f (patch)
treee4f332b45fe65e2a7a2451be5674f887b42bf199 /testsuite/tests/gadt/Gadt17_help.hs
parentebd422aed41048476aa61dd4c520d43becd78682 (diff)
downloadhaskell-16514f272fb42af6e9c7674a9bd6c9dce369231f.tar.gz
Move tests from tests/ghc-regress/* to just tests/*
Diffstat (limited to 'testsuite/tests/gadt/Gadt17_help.hs')
-rw-r--r--testsuite/tests/gadt/Gadt17_help.hs34
1 files changed, 34 insertions, 0 deletions
diff --git a/testsuite/tests/gadt/Gadt17_help.hs b/testsuite/tests/gadt/Gadt17_help.hs
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--- /dev/null
+++ b/testsuite/tests/gadt/Gadt17_help.hs
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+{-# LANGUAGE GADTs #-}
+{-# OPTIONS_GHC -O #-}
+
+module Gadt17_help (
+ TernOp (..), applyTernOp
+ ) where
+
+data TypeWitness a where
+ TWInt :: TypeWitness Int
+ TWBool :: TypeWitness Bool
+ TWFloat :: TypeWitness Float
+ TWDouble :: TypeWitness Double
+
+instance (Eq a) => Eq (TypeWitness a) where
+ (==) TWInt TWInt = True
+ (==) TWBool TWBool = True
+ (==) TWFloat TWFloat = True
+ (==) TWDouble TWDouble = True
+ (==) _ _ = False
+
+data TernOp a b c d where
+ OpIf :: TypeWitness a -> TernOp Bool a a a
+ OpTernFunc :: TypeWitness a -> TypeWitness b -> TypeWitness c
+ -> TypeWitness d -> (a -> b -> c -> d) -> TernOp a b c d
+
+instance Show (TernOp a b c d) where
+ show (OpIf {}) = "OpIf"
+ show (OpTernFunc {}) = "OpTernFunc <function>"
+
+
+applyTernOp :: TernOp a b c d -> a -> b -> c -> d
+applyTernOp (OpIf {}) cond x y = if (cond) then x else y
+applyTernOp (OpTernFunc _ _ _ _ f) x y z = f x y z
+