objective c - What are the differences between [[NSMutableArray alloc] init] and [@[] mutableCopy]? -

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nsmutablearray *myarray = [[nsmutablearray alloc] init];

vs

nsmutablearray *myarray = [@[] mutablecopy]

what differences between declaring arrays in these 2 separate ways?

think of 2nd line as:

nsmutablearray *myarray = [[[nsarray alloc] init] mutablecopy];

so clear difference 1st way more efficient , 2nd way needlessly creates object promptly discarded.


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