Repository : ssh://darcs.haskell.org//srv/darcs/testsuite On branch : master
http://hackage.haskell.org/trac/ghc/changeset/6e301a83e5162008b0fe7a63b0f3a7beaea112af >--------------------------------------------------------------- commit 6e301a83e5162008b0fe7a63b0f3a7beaea112af Author: Simon Peyton Jones <simo...@microsoft.com> Date: Tue Jan 8 23:46:37 2013 +0000 Test Trac #7279 >--------------------------------------------------------------- tests/typecheck/should_fail/T7279.hs | 6 ++++++ tests/typecheck/should_fail/T7279.stderr | 10 ++++++++++ tests/typecheck/should_fail/all.T | 1 + 3 files changed, 17 insertions(+), 0 deletions(-) diff --git a/tests/typecheck/should_fail/T7279.hs b/tests/typecheck/should_fail/T7279.hs new file mode 100644 index 0000000..f1cc9d7 --- /dev/null +++ b/tests/typecheck/should_fail/T7279.hs @@ -0,0 +1,6 @@ +{-# LANGUAGE UndecidableInstances #-} +module T7279 where + +data T a = MkT + +instance (Eq a, Show b) => Eq (T a) diff --git a/tests/typecheck/should_fail/T7279.stderr b/tests/typecheck/should_fail/T7279.stderr new file mode 100644 index 0000000..6af478e --- /dev/null +++ b/tests/typecheck/should_fail/T7279.stderr @@ -0,0 +1,10 @@ + +T7279.hs:6:10: + Could not deduce (Show b0) + arising from the ambiguity check for an instance declaration + from the context (Eq a, Show b) + bound by an instance declaration: (Eq a, Show b) => Eq (T a) + at T7279.hs:6:10-35 + The type variable `b0' is ambiguous + In the ambiguity check for: forall a b. (Eq a, Show b) => Eq (T a) + In the instance declaration for `Eq (T a)' diff --git a/tests/typecheck/should_fail/all.T b/tests/typecheck/should_fail/all.T index bbf6eb6..a4d0216 100644 --- a/tests/typecheck/should_fail/all.T +++ b/tests/typecheck/should_fail/all.T @@ -292,3 +292,4 @@ test('T7453', normal, compile_fail, ['']) test('T7525', normal, compile_fail, ['']) test('T7368a', normal, compile_fail, ['']) test('T7545', normal, compile_fail, ['']) +test('T7279', normal, compile_fail, ['']) _______________________________________________ Cvs-ghc mailing list Cvs-ghc@haskell.org http://www.haskell.org/mailman/listinfo/cvs-ghc
