T14773b.hs:4:10: warning: [-Woverlapping-patterns (in -Wdefault)]
    Pattern match is redundant
    In a pattern binding guards: = ...

T14773b.hs:4:10: warning: [-Wincomplete-patterns (in -Wextra)]
    Pattern match(es) are non-exhaustive
    In a pattern binding guards:
        Guards do not cover entire pattern space