Commit 23b0bf0c authored by Simon Peyton Jones's avatar Simon Peyton Jones
Browse files

Test Trac #7279

parent b5cf4978
{-# LANGUAGE UndecidableInstances #-}
module T7279 where
data T a = MkT
instance (Eq a, Show b) => Eq (T a)
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)'
......@@ -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, [''])
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment