first commit

app_vue/node_modules/handle-thing/lib/queue.js

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+function Queue () {
+  this.head = new Item('head', null)
+}
+module.exports = Queue
+
+Queue.prototype.append = function append (kind, value) {
+  var item = new Item(kind, value)
+  this.head.prepend(item)
+  return item
+}
+
+Queue.prototype.isEmpty = function isEmpty () {
+  return this.head.prev === this.head
+}
+
+Queue.prototype.first = function first () {
+  return this.head.next
+}
+
+function Item (kind, value) {
+  this.prev = this
+  this.next = this
+  this.kind = kind
+  this.value = value
+}
+
+Item.prototype.prepend = function prepend (other) {
+  other.prev = this.prev
+  other.next = this
+  other.prev.next = other
+  other.next.prev = other
+}
+
+Item.prototype.dequeue = function dequeue () {
+  var prev = this.prev
+  var next = this.next
+
+  prev.next = next
+  next.prev = prev
+  this.prev = this
+  this.next = this
+
+  return this.value
+}
+
+Item.prototype.isEmpty = function isEmpty () {
+  return this.prev === this
+}