Question

Am I allowed to re-use the same variable name in different for loops in Objective-C? For example:

// This doesn't give me an error but I feel like it should:

for(int i = 0; i < 10; i++){
    //do something
}

for (int i = 0; i < 5; i++){    // I'm using "i" again.  Is this allowed?
    //do something else
}

This compiles and seems to run fine, but I just want to make sure that this is legal and allowed without causing some sort of complication in my program. I’m newish to ObjC, but in Java I normally would get errors from this.

Answer 1

That should be fine. The scope of i in the snippet you show is limited to each of the for loops, so there’s no conflict. If you instead do it like this:

int i;
for (i = 0; i < 2; i++) {
    //...
}

int i;
for (i = 5; i < 10; i++) {
    //...
}

then you’ll have a problem because you’re declaring i twice in the same scope.