in reply to if and unless


Possibly the following is what you want. It depends on whether the 'something screwing up' happens during execution of your 'do something else' or whether it just happens to be an input into the whole condtional, as shown here:

if ((some condition) && !(some counter-condition)) { do something }
As has been obliquely pointed out, unless can really be thought of as the opposite of if, so your code is essentially two consecutive and unrelated conditionals.

Sorry if this is not what you're after. It's hard to be sure :-)