"While"-like structure in Velocity?

All,

I've searched the archives for "while" capabilities in Velocity, and
mostly the answers have been things like "that's beyond the scope of
Velocity... you want a real programming language for that".

I'd like to do something that naturally would use a while loop, but
perhaps someone can offer an alternative suggestion.

I need to traverse a queue, but that queue needs to be able to modify
itself during the processing. Basically, something like this:

while (!queue.empty) {
  // do something with the head element
  // possible enqueue some more items at the back
}

#foreach would be the way to do it if the queue didn't have to be
modified, but I'll get an exception if I try to traverse an iterator
over the queue and then modify it mid-flight.

Right now, I have this written as a JSP but I'd rather have it as a
Velocity template.

My only thought is to create an ugly class that implements Iterator and
wraps the queue but is much less strict than a standard iterator. Any
suggestions?

-chris

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