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T12918b.hs:8:11: error:
• The default type signature for bar1: forall b. b -> a
does not match its corresponding non-default type signature
• When checking the class method:
bar1 :: forall a b. Foo1 a => a -> b
In the class declaration for ‘Foo1’
T12918b.hs:12:11: error:
• The default type signature for bar2: forall x. x
does not match its corresponding non-default type signature
• When checking the class method:
bar2 :: forall a b. Foo1 a => a -> b
In the class declaration for ‘Foo1’
T12918b.hs:12:11: error:
• Could not deduce (Foo1 a0)
from the context: Foo1 a
bound by the type signature for:
bar2 :: forall a x. Foo1 a => x
at T12918b.hs:12:11-14
The type variable ‘a0’ is ambiguous
• In the ambiguity check for ‘bar2’
To defer the ambiguity check to use sites, enable AllowAmbiguousTypes
When checking the class method:
bar2 :: forall a b. Foo1 a => a -> b
In the class declaration for ‘Foo1’
T12918b.hs:16:11: error:
• The default type signature for bar3: a -> Int
does not match its corresponding non-default type signature
• When checking the class method:
bar3 :: forall a b. Foo1 a => a -> b
In the class declaration for ‘Foo1’
T12918b.hs:20:11: error:
• The default type signature for bar4: forall b. a -> b
does not match its corresponding non-default type signature
• When checking the class method:
bar4 :: forall a. Foo1 a => a -> Int
In the class declaration for ‘Foo1’
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