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| "use strict";
|
| var isFunction = require("../function/is-function");
|
| module.exports = function (executor) {
| var Constructor;
| if (isFunction(this)) {
| Constructor = this;
| } else if (typeof Promise === "function") {
| Constructor = Promise;
| } else {
| throw new TypeError("Could not resolve Promise constuctor");
| }
|
| var lazyThen;
| var promise = new Constructor(function (resolve, reject) {
| lazyThen = function (onSuccess, onFailure) {
| if (!hasOwnProperty.call(this, "then")) {
| // Sanity check
| throw new Error("Unexpected (inherited) lazy then invocation");
| }
|
| try {
| executor(resolve, reject);
| } catch (reason) {
| reject(reason);
| }
| delete this.then;
| return this.then(onSuccess, onFailure);
| };
| });
|
| return Object.defineProperty(promise, "then", {
| configurable: true,
| writable: true,
| value: lazyThen
| });
| };
|
|
