What if [super init] returns nil?

Question

Take the following code as an example.

- (id)init {
    self = [super init];
    if (self) {
        // code
    }
    return self;
}

I do not want nil to propagate the calling hierarchy. My initial idea is to throw an exception when self is nil, make a restore point, and abort.

Best ideas?

Answer 1

The NSObject implementation [super init]will never return zero. The underlying implementation simply returns self .

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:

NSError *error;
FooClass *myFoo = [[FooClass alloc] initWithContentsOfURL:blah error:&error]
if (myFoo == nil) {
  // ...
} else {
  // ...
}

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Answer 2

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Answer 3

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Answer 4

, "[super init]" , 20 - ( iOS), "nil" .

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In Apple's “Concepts in C Lens,” they suggest, “When you create an object, you should usually check if the return value is nil before continuing:”.