While loop is not iterating through all array elements

anonymous_user_1ed1c3df · February 16, 2017, 8:22am

I have a buff system I’m trying to prototype. I have a buff object being created and added to an array. I’m printing a list to the screen to see how many items are in the array. Then I’m iterating through the array and calling the Destroy method on all my buff objects. Weirdly not every object is being iterated. Only every other item and I don’t know why.

Created 5 buff objects that get added to an array.

Printed a list of the array which iterated through all 5 items.

Iterated again to call the Destroy method on each item which only called every other item.

Print of what’s remaining in the list.

Klateralus · February 16, 2017, 8:29am

Instead of WhileLoop is better to use For Each Loop

That’s node will do everything you need

anonymous_user_1ed1c3df · February 16, 2017, 9:09am

Same results.

anonymous_user_1ed1c3df · February 16, 2017, 9:16am

I think the issue is what array.Remove is doing. Seems to be resizing my list before I finish iterating through it. So how do I iterate through a list removing specific elements?

Klateralus · February 16, 2017, 9:28am

Oh, I see. Don’t remove elements from array when you iterate him, that breaks your cycle.

First iterate all components in array and destroy them.
Than clear the array.

anonymous_user_1ed1c3df · February 16, 2017, 9:47am

Finally!

I learned that removing the item at element i calls for the array to arrange itself so the item at element 0 that has been removed now contains the item at element 1, and by the time my iteration goes to 1, element 1 now contains what was in element 2, etc…

Okay, so since its doing that, I’ll just always get the element at 0 since all the elements will shuffle down after one is removed. My loop still only iterated 3 times. I was very confused. Then I tried the same logic in reverse always getting the last element in the array. Still only 3. So what the fat?

Seems loop nodes (For and ForEach) are constantly pooling new data for parameters during iteration instead of caching it in local scope like for(int i = 0; i < array.length; i++) would. So once I cached what array length is before my loop started, it began iterating as expected.

Loop nodes are kind of dumb.