Sometimes we can't figure out the type of the property propely from only the application:
/input/sudoku_props/checks/697b90e1/FakeCheckTarget697b90e1.hs:667:19: error:
• Ambiguous type variable ‘t0’ arising from a use of ‘prop'_anyBlock_withWrongNumberOfCells_isInvalid’
prevents the constraint ‘(Ord t0)’ from being solved.
Probable fix: use a type annotation to specify what ‘t0’ should be.
These potential instances exist:
instance (Ord a, Ord b) => Ord (Either a b)
-- Defined in ‘Data.Either’
instance Ord GeneralCategory -- Defined in ‘GHC.Unicode’
instance Ord Ordering -- Defined in ‘GHC.Classes’
...plus 24 others
...plus 92 instances involving out-of-scope types
(use -fprint-potential-instances to see them all)
• In the third argument of ‘qcWRes’, namely
‘(prop'_anyBlock_withWrongNumberOfCells_isInvalid
expr__isOkayBlock)’
In the second argument of ‘fmap’, namely
‘(qcWRes
(1000000) qc__
(prop'_anyBlock_withWrongNumberOfCells_isInvalid
expr__isOkayBlock))’
In the expression:
fmap
qcSuccess
(qcWRes
(1000000) qc__
(prop'_anyBlock_withWrongNumberOfCells_isInvalid
expr__isOkayBlock))
|
667 | (prop'_anyBlock_withWrongNumberOfCells_isInvalid
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...
Sometimes we can't figure out the type of the property propely from only the application: