[commit: ghc] master: Test Trac #9036 (c4e9f24)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/c4e9f243398942499c9f5e21318e6ceb048d5880/ghc

>---------------------------------------------------------------

commit c4e9f243398942499c9f5e21318e6ceb048d5880
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Apr 28 08:55:32 2014 +0100

    Test Trac #9036


>---------------------------------------------------------------

c4e9f243398942499c9f5e21318e6ceb048d5880
 testsuite/tests/indexed-types/should_fail/T9036.hs   |   18 ++++++++++++++++++
 .../tests/indexed-types/should_fail/T9036.stderr     |   12 ++++++++++++
 testsuite/tests/indexed-types/should_fail/all.T      |    1 +
 3 files changed, 31 insertions(+)

diff --git a/testsuite/tests/indexed-types/should_fail/T9036.hs b/testsuite/tests/indexed-types/should_fail/T9036.hs
new file mode 100644
index 0000000..550adb4
--- /dev/null
+++ b/testsuite/tests/indexed-types/should_fail/T9036.hs
@@ -0,0 +1,18 @@
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE TypeOperators #-}
+{-# LANGUAGE TypeFamilies #-}
+
+
+module T9036 where
+
+class UncurryM t where
+  type GetMonad t :: * -> *
+
+class Curry a b where
+  type Curried a b :: *
+
+gSimple :: String -> String -> [String]
+gSimple = simpleLogger (return ())
+
+simpleLogger :: Maybe (GetMonad t after) -> t `Curried` [t]
+simpleLogger _  _ = undefined
diff --git a/testsuite/tests/indexed-types/should_fail/T9036.stderr b/testsuite/tests/indexed-types/should_fail/T9036.stderr
new file mode 100644
index 0000000..2df53c7
--- /dev/null
+++ b/testsuite/tests/indexed-types/should_fail/T9036.stderr
@@ -0,0 +1,12 @@
+
+T9036.hs:17:17:
+    Couldn't match type ‘GetMonad t0’ with ‘GetMonad t’
+    NB: ‘GetMonad’ is a type function, and may not be injective
+    The type variable ‘t0’ is ambiguous
+    Expected type: Maybe (GetMonad t after) -> Curried t [t]
+      Actual type: Maybe (GetMonad t0 after) -> Curried t0 [t0]
+    In the ambiguity check for:
+      forall t after. Maybe (GetMonad t after) -> Curried t [t]
+    To defer the ambiguity check to use sites, enable AllowAmbiguousTypes
+    In the type signature for ‘simpleLogger’:
+      simpleLogger :: Maybe (GetMonad t after) -> t `Curried` [t]
diff --git a/testsuite/tests/indexed-types/should_fail/all.T b/testsuite/tests/indexed-types/should_fail/all.T
index 54a33cd..003b51d 100644
--- a/testsuite/tests/indexed-types/should_fail/all.T
+++ b/testsuite/tests/indexed-types/should_fail/all.T
@@ -119,4 +119,5 @@ test('T8129',
 test('T8368', normal, compile_fail, [''])
 test('T8368a', normal, compile_fail, [''])
 test('T8518', normal, compile_fail, [''])
+test('T9036', normal, compile_fail, [''])