skipLast.js 1.8 KB

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  1. /** PURE_IMPORTS_START tslib,_Subscriber,_util_ArgumentOutOfRangeError PURE_IMPORTS_END */
  2. import * as tslib_1 from "tslib";
  3. import { Subscriber } from '../Subscriber';
  4. import { ArgumentOutOfRangeError } from '../util/ArgumentOutOfRangeError';
  5. export function skipLast(count) {
  6. return function (source) { return source.lift(new SkipLastOperator(count)); };
  7. }
  8. var SkipLastOperator = /*@__PURE__*/ (function () {
  9. function SkipLastOperator(_skipCount) {
  10. this._skipCount = _skipCount;
  11. if (this._skipCount < 0) {
  12. throw new ArgumentOutOfRangeError;
  13. }
  14. }
  15. SkipLastOperator.prototype.call = function (subscriber, source) {
  16. if (this._skipCount === 0) {
  17. return source.subscribe(new Subscriber(subscriber));
  18. }
  19. else {
  20. return source.subscribe(new SkipLastSubscriber(subscriber, this._skipCount));
  21. }
  22. };
  23. return SkipLastOperator;
  24. }());
  25. var SkipLastSubscriber = /*@__PURE__*/ (function (_super) {
  26. tslib_1.__extends(SkipLastSubscriber, _super);
  27. function SkipLastSubscriber(destination, _skipCount) {
  28. var _this = _super.call(this, destination) || this;
  29. _this._skipCount = _skipCount;
  30. _this._count = 0;
  31. _this._ring = new Array(_skipCount);
  32. return _this;
  33. }
  34. SkipLastSubscriber.prototype._next = function (value) {
  35. var skipCount = this._skipCount;
  36. var count = this._count++;
  37. if (count < skipCount) {
  38. this._ring[count] = value;
  39. }
  40. else {
  41. var currentIndex = count % skipCount;
  42. var ring = this._ring;
  43. var oldValue = ring[currentIndex];
  44. ring[currentIndex] = value;
  45. this.destination.next(oldValue);
  46. }
  47. };
  48. return SkipLastSubscriber;
  49. }(Subscriber));
  50. //# sourceMappingURL=skipLast.js.map