RollYourOwnArrowType.dfy(6,5): Error: cannot find witness that shows type is inhabited; try giving a hint through a 'witness' or 'ghost witness' clause
Execution trace:
    (0,0): anon0
    (0,0): anon4_Else
RollYourOwnArrowType.dfy(141,16): Error: the given witness expression might not satisfy constraint
RollYourOwnArrowType.dfy(139,21): Related location
RollYourOwnArrowType.dfy(123,2): Related location
RollYourOwnArrowType.dfy(123,16): Related location
Execution trace:
    (0,0): anon0
    (0,0): anon4_Else

Dafny program verifier finished with 28 verified, 2 errors
