NSMutableArray removeObjectAtIndex:0 not behaving as expected

Question

I have this simple method to put the first element of an array at the end and move everything down by one index:

-(NSArray*)backUpNotes:(NSArray*)notes {
    NSMutableArray* newNotes = [NSMutableArray arrayWithArray:notes];
    Note* note = [newNotes objectAtIndex:0];
    [newNotes removeObjectAtIndex:0];
    [newNotes addObject:note];

    return (NSArray*)newNotes;
}

the array notes contains two Note* objects, Note A and Note B. after the line

Note* note = [newNotes objectAtIndex:0];

note contains Note A -- as expected. After the line

[newNotes removeObjectAtIndex:0];

newNotes ONLY contains Note A --- This is NOT expected. Note A is at index 0, and I can see that from the debugger. If I instead do

[newNotes removeObjectAtIndex:1];

newNotes still ONLY contains Note A -- That is expected, since I'm removing note B in that case. It seems to me that I cannot for the life of me remove Note A from this array. I even tried doing:

[newNotes removeObject:note];

and still having newNotes containing ONLY note A -- definitely unexpected.

Any insight would be amazing.

Answer 1

Try this:

NSMutableArray* newNotes = [NSMutableArray arrayWithArray:notes];
for (Note *n in newNotes) {
    if ([n isEqual:note]) {
        [newNotes removeObject:n];
        break;
    }
}

Or:

int x = 0;
NSMutableArray* newNotes = [NSMutableArray arrayWithArray:notes];
for (Note *n in newNotes) {
    if ([n isEqual:note]) {
        break;
    }
    ++x;
}
[newNotes removeObjectAtIndex:x];