objective c - Inline condition checking - what is it? [duplicate]

Question

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What does the question mark and the colon (?: ternary operator) mean in objective-c? (13 answers)

Closed 9 years ago.

Please forgive the title, it's probably wrong, since I don't know anything about it. Because of that, I didn't have any search terms to look it up, so could someone explain me what does this mean and how to use it? I just picked this example as I recently found it.

id item = [arr count] > 0 ? arr[0] : nil;

Answer 1

This line is the same as

id item;
if ([arr count] > 0) {
   item = arr[0];
}else{
   item = nil;
}