[commit: testsuite] master: Test Trac #7264 (a457a9d)

Repository : ssh://darcs.haskell.org//srv/darcs/testsuite

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/a457a9d3681dd00705c1c5775afb84fd85ac554e

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

commit a457a9d3681dd00705c1c5775afb84fd85ac554e
Author: Simon Peyton Jones <[email protected]>
Date:   Wed Oct 31 09:49:48 2012 +0000

    Test Trac #7264

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

 tests/typecheck/should_fail/T7264.hs     |   13 +++++++++++++
 tests/typecheck/should_fail/T7264.stderr |   17 +++++++++++++++++
 tests/typecheck/should_fail/all.T        |    1 +
 3 files changed, 31 insertions(+), 0 deletions(-)

diff --git a/tests/typecheck/should_fail/T7264.hs b/tests/typecheck/should_fail/T7264.hs
new file mode 100644
index 0000000..b9d3624
--- /dev/null
+++ b/tests/typecheck/should_fail/T7264.hs
@@ -0,0 +1,13 @@
+{-# LANGUAGE RankNTypes #-}
+module T7264 where
+
+data Foo = Foo (forall r . r -> String)
+
+mmap :: (a->b) -> Maybe a -> Maybe b
+mmap f (Just x) = Just (f x)
+mmap f Nothing  = Nothing
+
+-- mkFoo2 :: (forall r. r -> String) -> Maybe Foo
+-- Should be rejected because it requires instantiating
+-- mmap at a polymorphic type
+mkFoo2 val = mmap Foo (Just val)
diff --git a/tests/typecheck/should_fail/T7264.stderr b/tests/typecheck/should_fail/T7264.stderr
new file mode 100644
index 0000000..8ed4ec2
--- /dev/null
+++ b/tests/typecheck/should_fail/T7264.stderr
@@ -0,0 +1,17 @@
+
+T7264.hs:13:19:
+    Couldn't match type `a' with `forall r. r -> String'
+      `a' is untouchable
+        inside the constraints ()
+        bound by the inferred type of mkFoo2 :: a -> Maybe Foo
+        at T7264.hs:13:1-32
+      `a' is a rigid type variable bound by
+          the inferred type of mkFoo2 :: a -> Maybe Foo at T7264.hs:13:1
+    Expected type: a -> Foo
+      Actual type: (forall r. r -> String) -> Foo
+    Relevant bindings include
+      mkFoo2 :: a -> Maybe Foo (bound at T7264.hs:13:1)
+      val :: a (bound at T7264.hs:13:8)
+    In the first argument of `mmap', namely `Foo'
+    In the expression: mmap Foo (Just val)
+    In an equation for `mkFoo2': mkFoo2 val = mmap Foo (Just val)
diff --git a/tests/typecheck/should_fail/all.T b/tests/typecheck/should_fail/all.T
index cbc393b..a621298 100644
--- a/tests/typecheck/should_fail/all.T
+++ b/tests/typecheck/should_fail/all.T
@@ -284,3 +284,4 @@ test('T7175', normal, compile_fail, [''])
 test('T7210', normal, compile_fail, [''])
 test('T6161', normal, compile_fail, [''])
 test('T7368', normal, compile_fail, [''])
+test('T7264', normal, compile_fail, [''])