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T14584.hs:56:41: warning: [-Wdeferred-type-errors (in -Wdefault)]
• Could not deduce: m1 ~ *
from the context: (Action act, Monoid a, Good m1)
bound by the instance declaration at T14584.hs:54:10-89
‘m1’ is a rigid type variable bound by
the instance declaration
at T14584.hs:54:10-89
When matching types
a :: *
a0 :: m
Expected type: Sing a0
Actual type: Sing a
• In the second argument of ‘fromSing’, namely
‘(sing @m @a :: Sing _)’
In the fourth argument of ‘act’, namely
‘(fromSing @m (sing @m @a :: Sing _))’
In the expression:
act @_ @_ @act (fromSing @m (sing @m @a :: Sing _))
• Relevant bindings include
monHom :: a -> a (bound at T14584.hs:56:3)
T14584.hs:56:41: warning: [-Wdeferred-type-errors (in -Wdefault)]
• Could not deduce: a ~~ a0
from the context: (Action act, Monoid a, Good m1)
bound by the instance declaration at T14584.hs:54:10-89
‘a’ is a rigid type variable bound by
the instance declaration
at T14584.hs:54:10-89
Expected type: Sing a0
Actual type: Sing a
• In the second argument of ‘fromSing’, namely
‘(sing @m @a :: Sing _)’
In the fourth argument of ‘act’, namely
‘(fromSing @m (sing @m @a :: Sing _))’
In the expression:
act @_ @_ @act (fromSing @m (sing @m @a :: Sing _))
• Relevant bindings include
monHom :: a -> a (bound at T14584.hs:56:3)
T14584.hs:56:41: warning: [-Wdeferred-type-errors (in -Wdefault)]
• Could not deduce (SingI a) arising from a use of ‘sing’
from the context: (Action act, Monoid a, Good m1)
bound by the instance declaration at T14584.hs:54:10-89
• In the second argument of ‘fromSing’, namely
‘(sing @m @a :: Sing _)’
In the fourth argument of ‘act’, namely
‘(fromSing @m (sing @m @a :: Sing _))’
In the expression:
act @_ @_ @act (fromSing @m (sing @m @a :: Sing _))
T14584.hs:56:60: warning: [-Wpartial-type-signatures (in -Wdefault)]
• Found type wildcard ‘_’ standing for ‘a0 :: m’
Where: ‘a0’ is an ambiguous type variable
‘m’ is a rigid type variable bound by
the instance declaration
at T14584.hs:54:10-89
• In an expression type signature: Sing _
In the second argument of ‘fromSing’, namely
‘(sing @m @a :: Sing _)’
In the fourth argument of ‘act’, namely
‘(fromSing @m (sing @m @a :: Sing _))’
• Relevant bindings include
monHom :: a -> a (bound at T14584.hs:56:3)
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