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| ; | |
| Object.defineProperty(exports, "__esModule", { | |
| value: true | |
| }); | |
| // Simple doubly linked list (https://en.wikipedia.org/wiki/Doubly_linked_list) implementation | |
| // used for queues. This implementation assumes that the node provided by the user can be modified | |
| // to adjust the next and last properties. We implement only the minimal functionality | |
| // for queue support. | |
| class DLL { | |
| constructor() { | |
| this.head = this.tail = null; | |
| this.length = 0; | |
| } | |
| removeLink(node) { | |
| if (node.prev) node.prev.next = node.next;else this.head = node.next; | |
| if (node.next) node.next.prev = node.prev;else this.tail = node.prev; | |
| node.prev = node.next = null; | |
| this.length -= 1; | |
| return node; | |
| } | |
| empty() { | |
| while (this.head) this.shift(); | |
| return this; | |
| } | |
| insertAfter(node, newNode) { | |
| newNode.prev = node; | |
| newNode.next = node.next; | |
| if (node.next) node.next.prev = newNode;else this.tail = newNode; | |
| node.next = newNode; | |
| this.length += 1; | |
| } | |
| insertBefore(node, newNode) { | |
| newNode.prev = node.prev; | |
| newNode.next = node; | |
| if (node.prev) node.prev.next = newNode;else this.head = newNode; | |
| node.prev = newNode; | |
| this.length += 1; | |
| } | |
| unshift(node) { | |
| if (this.head) this.insertBefore(this.head, node);else setInitial(this, node); | |
| } | |
| push(node) { | |
| if (this.tail) this.insertAfter(this.tail, node);else setInitial(this, node); | |
| } | |
| shift() { | |
| return this.head && this.removeLink(this.head); | |
| } | |
| pop() { | |
| return this.tail && this.removeLink(this.tail); | |
| } | |
| toArray() { | |
| return [...this]; | |
| } | |
| *[Symbol.iterator]() { | |
| var cur = this.head; | |
| while (cur) { | |
| yield cur.data; | |
| cur = cur.next; | |
| } | |
| } | |
| remove(testFn) { | |
| var curr = this.head; | |
| while (curr) { | |
| var { next } = curr; | |
| if (testFn(curr)) { | |
| this.removeLink(curr); | |
| } | |
| curr = next; | |
| } | |
| return this; | |
| } | |
| } | |
| exports.default = DLL; | |
| function setInitial(dll, node) { | |
| dll.length = 1; | |
| dll.head = dll.tail = node; | |
| } | |
| module.exports = exports.default; |