*** Failed! Falsifiable (after 75 tests):
\x _ -> case x of
        0 -> 1
        _ -> 0
0
[0,0]

+++ OK, passed 200 tests.
*** Failed! Falsifiable (after 36 tests):
\_ -> 0
\x -> case x of
      0 -> True
      _ -> False
[1]

*** Failed! Falsifiable (after 1 tests):
(\_ -> 0) (\_ -> 0)
*** Failed! Falsifiable (after 1 tests):
(\_ -> 0) (0,0)