T20768_fail.hs:7:16: error: [GHC-83865]
    • Couldn't match expected type ‘Bool’ with actual type ‘Char’
    • In the expression: 'c'
      In a stmt of a pattern guard for
                     a \cases alternative:
        'c'
      In a \cases alternative: | 'c' -> "foo"

T20768_fail.hs:9:1: error: [GHC-83865]
    • Couldn't match expected type: IO t0
                  with actual type: a0 -> m0 ()
    • When checking the type of the IO action ‘main’

T20768_fail.hs:11:11: error: [GHC-91938]
    • \cases alternatives have different numbers of arguments
        T20768_fail.hs:11:18-33
        T20768_fail.hs:12:18-31
    • In the second argument of ‘(&)’, namely
        ‘\cases
           1 2 -> return ()
           1 -> return ()’
      In the expression:
        1 & \cases
              1 2 -> return ()
              1 -> return ()
      In an equation for ‘foo’:
          foo
            = 1 & \cases
                    1 2 -> return ()
                    1 -> return ()