SOUTHERNCO\x2mjbyrn 7efe7605b8 Template Upload
2017-05-17 13:45:25 -04:00

58 lines
2.1 KiB
JavaScript

"use strict";
var __extends = (this && this.__extends) || function (d, b) {
for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
var Subscriber_1 = require('../Subscriber');
/**
* Similar to the well known `Array.prototype.map` function, this operator
* applies a projection to each value and emits that projection in the returned observable
*
* <img src="./img/map.png" width="100%">
*
* @param {Function} project the function to create projection
* @param {any} [thisArg] an optional argument to define what `this` is in the project function
* @returns {Observable} a observable of projected values
*/
function map(project, thisArg) {
if (typeof project !== 'function') {
throw new TypeError('argument is not a function. Are you looking for `mapTo()`?');
}
return this.lift(new MapOperator(project, thisArg));
}
exports.map = map;
var MapOperator = (function () {
function MapOperator(project, thisArg) {
this.project = project;
this.thisArg = thisArg;
}
MapOperator.prototype.call = function (subscriber) {
return new MapSubscriber(subscriber, this.project, this.thisArg);
};
return MapOperator;
}());
var MapSubscriber = (function (_super) {
__extends(MapSubscriber, _super);
function MapSubscriber(destination, project, thisArg) {
_super.call(this, destination);
this.project = project;
this.count = 0;
this.thisArg = thisArg || this;
}
// NOTE: This looks unoptimized, but it's actually purposefully NOT
// using try/catch optimizations.
MapSubscriber.prototype._next = function (value) {
var result;
try {
result = this.project.call(this.thisArg, value, this.count++);
}
catch (err) {
this.destination.error(err);
return;
}
this.destination.next(result);
};
return MapSubscriber;
}(Subscriber_1.Subscriber));
//# sourceMappingURL=map.js.map