{"version":3,"file":"scan.js","sourceRoot":"","sources":["../../src/operators/scan.ts"],"names":[],"mappings":";;;;;;AAEA,2BAA2B,eAAe,CAAC,CAAA;AAO3C,mCAAmC;AAEnC;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;GAoCG;AACH,cAA2B,WAAmD,EAAE,IAAY;IAC1F,IAAI,OAAO,GAAG,KAAK,CAAC;IACpB,gEAAgE;IAChE,qDAAqD;IACrD,sEAAsE;IACtE,oEAAoE;IACpE,+EAA+E;IAC/E,EAAE,CAAC,CAAC,SAAS,CAAC,MAAM,IAAI,CAAC,CAAC,CAAC,CAAC;QAC1B,OAAO,GAAG,IAAI,CAAC;IACjB,CAAC;IAED,MAAM,CAAC,8BAA8B,MAAqB;QACxD,MAAM,CAAC,MAAM,CAAC,IAAI,CAAC,IAAI,YAAY,CAAC,WAAW,EAAE,IAAI,EAAE,OAAO,CAAC,CAAC,CAAC;IACnE,CAAC,CAAC;AACJ,CAAC;AAde,YAAI,OAcnB,CAAA;AAED;IACE,sBAAoB,WAAmD,EAAU,IAAY,EAAU,OAAwB;QAAhC,uBAAgC,GAAhC,eAAgC;QAA3G,gBAAW,GAAX,WAAW,CAAwC;QAAU,SAAI,GAAJ,IAAI,CAAQ;QAAU,YAAO,GAAP,OAAO,CAAiB;IAAG,CAAC;IAEnI,2BAAI,GAAJ,UAAK,UAAyB,EAAE,MAAW;QACzC,MAAM,CAAC,MAAM,CAAC,SAAS,CAAC,IAAI,cAAc,CAAC,UAAU,EAAE,IAAI,CAAC,WAAW,EAAE,IAAI,CAAC,IAAI,EAAE,IAAI,CAAC,OAAO,CAAC,CAAC,CAAC;IACrG,CAAC;IACH,mBAAC;AAAD,CAAC,AAND,IAMC;AAED;;;;GAIG;AACH;IAAmC,kCAAa;IAY9C,wBAAY,WAA0B,EAAU,WAAmD,EAAU,KAAY,EACrG,OAAgB;QAClC,kBAAM,WAAW,CAAC,CAAC;QAF2B,gBAAW,GAAX,WAAW,CAAwC;QAAU,UAAK,GAAL,KAAK,CAAO;QACrG,YAAO,GAAP,OAAO,CAAS;QAZ5B,UAAK,GAAW,CAAC,CAAC;IAc1B,CAAC;IAZD,sBAAI,gCAAI;aAAR;YACE,MAAM,CAAC,IAAI,CAAC,KAAK,CAAC;QACpB,CAAC;aAED,UAAS,KAAY;YACnB,IAAI,CAAC,OAAO,GAAG,IAAI,CAAC;YACpB,IAAI,CAAC,KAAK,GAAG,KAAK,CAAC;QACrB,CAAC;;;OALA;IAYS,8BAAK,GAAf,UAAgB,KAAQ;QACtB,EAAE,CAAC,CAAC,CAAC,IAAI,CAAC,OAAO,CAAC,CAAC,CAAC;YAClB,IAAI,CAAC,IAAI,GAAG,KAAK,CAAC;YAClB,IAAI,CAAC,WAAW,CAAC,IAAI,CAAC,KAAK,CAAC,CAAC;QAC/B,CAAC;QAAC,IAAI,CAAC,CAAC;YACN,MAAM,CAAC,IAAI,CAAC,QAAQ,CAAC,KAAK,CAAC,CAAC;QAC9B,CAAC;IACH,CAAC;IAEO,iCAAQ,GAAhB,UAAiB,KAAQ;QACvB,IAAM,KAAK,GAAG,IAAI,CAAC,KAAK,EAAE,CAAC;QAC3B,IAAI,MAAW,CAAC;QAChB,IAAI,CAAC;YACH,MAAM,GAAG,IAAI,CAAC,WAAW,CAAI,IAAI,CAAC,IAAI,EAAE,KAAK,EAAE,KAAK,CAAC,CAAC;QACxD,CAAE;QAAA,KAAK,CAAC,CAAC,GAAG,CAAC,CAAC,CAAC;YACb,IAAI,CAAC,WAAW,CAAC,KAAK,CAAC,GAAG,CAAC,CAAC;QAC9B,CAAC;QACD,IAAI,CAAC,IAAI,GAAG,MAAM,CAAC;QACnB,IAAI,CAAC,WAAW,CAAC,IAAI,CAAC,MAAM,CAAC,CAAC;IAChC,CAAC;IACH,qBAAC;AAAD,CAAC,AArCD,CAAmC,uBAAU,GAqC5C","sourcesContent":["import { Operator } from '../Operator';\nimport { Observable } from '../Observable';\nimport { Subscriber } from '../Subscriber';\nimport { OperatorFunction, MonoTypeOperatorFunction } from '../interfaces';\n\n/* tslint:disable:max-line-length */\nexport function scan<T>(accumulator: (acc: T, value: T, index: number) => T, seed?: T): MonoTypeOperatorFunction<T>;\nexport function scan<T>(accumulator: (acc: T[], value: T, index: number) => T[], seed?: T[]): OperatorFunction<T, T[]>;\nexport function scan<T, R>(accumulator: (acc: R, value: T, index: number) => R, seed?: R): OperatorFunction<T, R>;\n/* tslint:enable:max-line-length */\n\n/**\n * Applies an accumulator function over the source Observable, and returns each\n * intermediate result, with an optional seed value.\n *\n * <span class=\"informal\">It's like {@link reduce}, but emits the current\n * accumulation whenever the source emits a value.</span>\n *\n * <img src=\"./img/scan.png\" width=\"100%\">\n *\n * Combines together all values emitted on the source, using an accumulator\n * function that knows how to join a new source value into the accumulation from\n * the past. Is similar to {@link reduce}, but emits the intermediate\n * accumulations.\n *\n * Returns an Observable that applies a specified `accumulator` function to each\n * item emitted by the source Observable. If a `seed` value is specified, then\n * that value will be used as the initial value for the accumulator. If no seed\n * value is specified, the first item of the source is used as the seed.\n *\n * @example <caption>Count the number of click events</caption>\n * var clicks = Rx.Observable.fromEvent(document, 'click');\n * var ones = clicks.mapTo(1);\n * var seed = 0;\n * var count = ones.scan((acc, one) => acc + one, seed);\n * count.subscribe(x => console.log(x));\n *\n * @see {@link expand}\n * @see {@link mergeScan}\n * @see {@link reduce}\n *\n * @param {function(acc: R, value: T, index: number): R} accumulator\n * The accumulator function called on each source value.\n * @param {T|R} [seed] The initial accumulation value.\n * @return {Observable<R>} An observable of the accumulated values.\n * @method scan\n * @owner Observable\n */\nexport function scan<T, R>(accumulator: (acc: R, value: T, index: number) => R, seed?: T | R): OperatorFunction<T, R> {\n  let hasSeed = false;\n  // providing a seed of `undefined` *should* be valid and trigger\n  // hasSeed! so don't use `seed !== undefined` checks!\n  // For this reason, we have to check it here at the original call site\n  // otherwise inside Operator/Subscriber we won't know if `undefined`\n  // means they didn't provide anything or if they literally provided `undefined`\n  if (arguments.length >= 2) {\n    hasSeed = true;\n  }\n\n  return function scanOperatorFunction(source: Observable<T>): Observable<R> {\n    return source.lift(new ScanOperator(accumulator, seed, hasSeed));\n  };\n}\n\nclass ScanOperator<T, R> implements Operator<T, R> {\n  constructor(private accumulator: (acc: R, value: T, index: number) => R, private seed?: T | R, private hasSeed: boolean = false) {}\n\n  call(subscriber: Subscriber<R>, source: any): any {\n    return source.subscribe(new ScanSubscriber(subscriber, this.accumulator, this.seed, this.hasSeed));\n  }\n}\n\n/**\n * We need this JSDoc comment for affecting ESDoc.\n * @ignore\n * @extends {Ignored}\n */\nclass ScanSubscriber<T, R> extends Subscriber<T> {\n  private index: number = 0;\n\n  get seed(): T | R {\n    return this._seed;\n  }\n\n  set seed(value: T | R) {\n    this.hasSeed = true;\n    this._seed = value;\n  }\n\n  constructor(destination: Subscriber<R>, private accumulator: (acc: R, value: T, index: number) => R, private _seed: T | R,\n              private hasSeed: boolean) {\n    super(destination);\n  }\n\n  protected _next(value: T): void {\n    if (!this.hasSeed) {\n      this.seed = value;\n      this.destination.next(value);\n    } else {\n      return this._tryNext(value);\n    }\n  }\n\n  private _tryNext(value: T): void {\n    const index = this.index++;\n    let result: any;\n    try {\n      result = this.accumulator(<R>this.seed, value, index);\n    } catch (err) {\n      this.destination.error(err);\n    }\n    this.seed = result;\n    this.destination.next(result);\n  }\n}\n"]}