Error found:
in module Main
at tests/purs/failing/4466.purs:15:44 - 15:67 (line 15, column 44 - line 15, column 67)

  A case expression could not be determined to cover all inputs.
  The following additional cases are required to cover all inputs:

    { sound: Quack }
    { sound: Bark }

  Alternatively, add a Partial constraint to the type of the enclosing value.

while checking that type Partial => t0
  is at least as general as type Boolean
while checking that expression case $0 of              
                                 { sound: Moo } -> true
  has type Boolean
in value declaration animalFunc

where t0 is an unknown type

See https://github.com/purescript/documentation/blob/master/errors/NoInstanceFound.md for more information,
or to contribute content related to this error.