queue.lua


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local cqueues = require'cqueues'
local condition = require'cqueues.condition'
local cqaux = require'cqueues.auxlib'

local Queue = {}

function Queue.make()
	return setmetatable({
		items = {},
		cv = condition.new(),
	}, {__index=Queue})
end

function Queue.enqueue(self, item)
	table.insert(self.items, item)
	self.cv:signal()
end

function Queue.iter(self)
	return cqaux.wrap(function()
		while true do
			while #self.items > 0 do
				local items = self.items
				self.items = {} -- the old switcheroo
				for _, item in ipairs(items) do
					coroutine.yield(item)
				end
			end
			self.cv:wait()
		end
	end)
end


return Queue