Is it safe to use removeObject: during enumerateObjectsUsingBlock:?

foundation, nsarray, objective-c

Solution

I think this should not be done.

As in enumeration the object is treated as const.

I tried same code, I received following error:

Collection <__NSArrayM: 0x10053b8d0> was mutated while being enumerated.

The Code:

NSMutableArray *mutableArray=[NSMutableArray new];
[mutableArray addObject:@"A"];
[mutableArray addObject:@"Ab"];
[mutableArray addObject:@"Ac"];
[mutableArray addObject:@"Ad"];

[mutableArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
    // do some stuff to obj before removing it
    [mutableArray removeObject:obj];
    NSLog(@"--->%@",mutableArray);
}];

Problem

This code runs without crashing and I don't see anything in the documentation, but is it really safe? ``` [mutableArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) { // do some stuff to obj before removing it [mutableArray removeObject:obj]; }]; ```

Original source

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