Question

Ok, say I do this.

NSMutableArray *array1=[NSMutableArray arrayWithObjects:@"poop", @"on", @"your", @"face", nil];

NSMutableArray *array2=array1;


[array2 removeAllObjects];

now does array1 have objects in it?

Answer 1

NSMutableArray *array1 = [NSMutableArray arrayWithObjects:@"one", @"two", nil];

Creates a mutable array object in memory with strings @”one and @”two” ..and make an array object pointer array1 point to that object in memory.

NSMutableArray *array2 = array1;

Create another pointer array2 of type NSMutableArray, and make it point to the same object in memory that array1 is pointing to.

[array2 removeAllObjects];

Remove all strings from the mutable Array object that is pointed to by array2

Now since array1 and array2 points to the same object in memory, both array1 and array2 will now point to a mutable array object in memory that has no objects in it.