About Swift: Execution was interrupted, reason: EXC_BAD_INSTRUCTION (code=EXC_1386_INVOP, subcode=0x0)

Question

I am just learning to code so I decided to start with Swift. I am following the tour that mac has for it at here and I am at the section where it is calculating a sum of num

Answer 1

For me this error happened because an implicitly unwrapped property was not set. Setting it would fix the issue.