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POClean solution to this ruby iterator trickiness?
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copied!<pre><code>k = [1,2,3,4,5] for n in k puts n if n == 2 k.delete(n) end end puts k.join(",") # Result: # 1 # 2 # 4 # 5 # [1,3,4,5] # Desired: # 1 # 2 # 3 # 4 # 5 # [1,3,4,5] </code></pre> <p>This same effect happens with the other array iterator, k.each:</p> <pre><code>k = [1,2,3,4,5] k.each do |n| puts n if n == 2 k.delete(n) end end puts k.join(",") </code></pre> <p>has the same output.</p> <p>The reason this is happening is pretty clear...Ruby doesn't actually iterate through the objects stored in the array, but rather just turns it into a pretty array index iterator, starting at index 0 and each time increasing the index until it's over. But when you delete an item, it still increments the index, so it doesn't evaluate the same index twice, which I want it to.</p> <p>This <em>might</em> not be what's happening, but it's the best I can think of.</p> <p>Is there a clean way to do this? Is there already a built-in iterator that can do this? Or will I have to dirty it up and do an array index iterator, and not increment when the item is deleted? (or iterate through a clone of the array, and delete from the original array)</p> <hr> <p><strong>Clarification</strong></p> <p>I don't simply want to delete items from an array; sorry if that was clear. What I'd want to do is iterate through each element, and "process" it; this process might sometimes delete it. To be more accurate:</p> <pre><code>class Living_Thing def initialize tracker,id @tracker = tracker @id = id @tracker << self end def process do_stuff puts @id if @id == 2 die end end def die do_stuff_to_die @tracker.delete(self) end def inspect @id end end tracking_array = Array.new() foo = Living_Thing.new(tracking_array,1) bar = Living_Thing.new(tracking_array,2) rab = Living_Thing.new(tracking_array,3) oof = Living_Thing.new(tracking_array,4) puts tracking_array.join(",") # => [1, 2, 3, 4] for n in tracking_array n.process end # result: only foo, bar, and oof are processed </code></pre> <p>Ideally, I'd want all items in tracking_array to be processed.</p> <p>When Living_Thing is removed from tracking_array, Living_Thing#die <em>must</em> be called; do_stuff_to_die cleans up things that have to be claned up.</p>

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