NSMutableArray arrayWithArray: vs initWithArray:

Question

They work in my application without any noticeable difference:

1)

theArray = [[NSMutableArray alloc] initWithArray:[NSKeyedUnarchiver unarchiveObjectWithData:theData]];

2)

theArray = [NSMutableArray arrayWithArray:[NSKeyedUnarchiver unarchiveObjectWithData:theData]];
[theArray retain];

However, are they really equivalent? (1) has a alloc statement, while (2) does not. Preferred than another?

Answer 1

The effect is the same. But (2) is less efficient (convenient method = alloc + init + autorelease).

• alloc → INIT
• alloc -> init -> autorelease -> save

The preferred way is not to copy the array.

theArray = [[NSKeyedUnarchiver unarchiveObjectWithData:theData] retain];

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