32 lines
663 B
Lua
32 lines
663 B
Lua
--- A Queue implementation, taken & adapted from https://www.lua.org/pil/11.4.html
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-- @module worldeditadditions.utils.queue
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local Queue = {}
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function Queue.new()
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return { first = 0, last = -1 }
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end
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function Queue.enqueue(queue, value)
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local new_last = queue.last + 1
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queue.last = new_last
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queue[new_last] = value
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end
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function Queue.is_empty(queue)
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return new_first > queue.last
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end
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function Queue.dequeue(queue)
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local first = queue.first
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if Queue.is_empty(queue) then
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error("Error: The queue is empty!")
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end
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local value = queue[first]
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queue[first] = nil -- Help the garbage collector out
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list.first = first + 1
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return value
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end
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return Queue
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