Class AwaitableQueue<T>

Example

import { assertEquals } from "jsr:@std/assert"

const
	queue = new AwaitableQueue<string>(),
	promise1 = queue.shift(),
	promise2 = queue.shift()

assertEquals(queue.getSize(), -2)

queue.push("hello")
assertEquals(await promise1, "hello")
assertEquals(queue.getSize(), -1)

queue.push("world")
assertEquals(await promise2, "world")
assertEquals(queue.getSize(), 0)

queue.push("abcd")
assertEquals(queue.getSize(), 1)
// notice that when extra items are present,
// an immediate value is returned rather than a promise.
assertEquals(queue.shift(), "abcd")

queue.push("1", "2", "3")
// dump all immediately available items, clearing off the internal list.
assertEquals(queue.dump(), ["1", "2", "3"])
assertEquals(queue.dump(), []) // nothing else to dump.

const
	promise3 = queue.shift(),
	promise4 = queue.shift(),
	promise5 = queue.shift(),
	// drop all promise resolvers, clearing off the internal list.
	[resolve3, resolve4, resolve5] = queue.drop()

assertEquals(queue.drop(), []) // no more promise resolvers remain to be dropped.
queue.push("1", "2", "3", "4", "5")
assertEquals(queue.shift(), "1")
assertEquals(queue.shift(), "2")

// `promise3` to `promise5` remain unresolved right now.
// but since we don't want forever hagging promises, we will resolve them below: 
resolve3(await queue.shift())
resolve4(await queue.shift())
resolve5(await queue.shift())
assertEquals(await promise3, "3")
assertEquals(await promise4, "4")
assertEquals(await promise5, "5")
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