Error found:
in module Main
at tests/purs/failing/438.purs:15:11 - 15:25 (line 15, column 11 - line 15, column 25)

  Type class instance for
                                  
    Data.Eq.Eq (Array (Fix Array))
                                  
  is possibly infinite.

while solving type class constraint
                        
  Data.Eq.Eq (Fix Array)
                        
while applying a function eq
  of type Eq t0 => t0 -> t0 -> Boolean
  to argument In []
while inferring the type of eq (In [])
in value declaration example

where t0 is an unknown type

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