
<interactive>:8:12:
    Couldn't match expected type ‛main::Interactive.Planet’
                with actual type ‛Planet’
    In the second argument of ‛(==)’, namely ‛Mercury’
    In the expression: mercury == Mercury
    In an equation for ‛it’: it = mercury == Mercury

<interactive>:10:10:
    Couldn't match expected type ‛Planet’
                with actual type ‛main::Interactive.Planet’
    In the second argument of ‛(==)’, namely ‛Earth’
    In the expression: Venus == Earth
    In an equation for ‛it’: it = Venus == Earth