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[yaffs-website] / node_modules / es6-promise / lib / es6-promise / promise / race.js

diff --git a/node_modules/es6-promise/lib/es6-promise/promise/race.js b/node_modules/es6-promise/lib/es6-promise/promise/race.js
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+import {
+  isArray
+} from "../utils";
+
+/**
+  `Promise.race` returns a new promise which is settled in the same way as the
+  first passed promise to settle.
+
+  Example:
+
+  ```javascript
+  let promise1 = new Promise(function(resolve, reject){
+    setTimeout(function(){
+      resolve('promise 1');
+    }, 200);
+  });
+
+  let promise2 = new Promise(function(resolve, reject){
+    setTimeout(function(){
+      resolve('promise 2');
+    }, 100);
+  });
+
+  Promise.race([promise1, promise2]).then(function(result){
+    // result === 'promise 2' because it was resolved before promise1
+    // was resolved.
+  });
+  ```
+
+  `Promise.race` is deterministic in that only the state of the first
+  settled promise matters. For example, even if other promises given to the
+  `promises` array argument are resolved, but the first settled promise has
+  become rejected before the other promises became fulfilled, the returned
+  promise will become rejected:
+
+  ```javascript
+  let promise1 = new Promise(function(resolve, reject){
+    setTimeout(function(){
+      resolve('promise 1');
+    }, 200);
+  });
+
+  let promise2 = new Promise(function(resolve, reject){
+    setTimeout(function(){
+      reject(new Error('promise 2'));
+    }, 100);
+  });
+
+  Promise.race([promise1, promise2]).then(function(result){
+    // Code here never runs
+  }, function(reason){
+    // reason.message === 'promise 2' because promise 2 became rejected before
+    // promise 1 became fulfilled
+  });
+  ```
+
+  An example real-world use case is implementing timeouts:
+
+  ```javascript
+  Promise.race([ajax('foo.json'), timeout(5000)])
+  ```
+
+  @method race
+  @static
+  @param {Array} promises array of promises to observe
+  Useful for tooling.
+  @return {Promise} a promise which settles in the same way as the first passed
+  promise to settle.
+*/
+export default function race(entries) {
+  /*jshint validthis:true */
+  let Constructor = this;
+
+  if (!isArray(entries)) {
+    return new Constructor((_, reject) => reject(new TypeError('You must pass an array to race.')));
+  } else {
+    return new Constructor((resolve, reject) => {
+      let length = entries.length;
+      for (let i = 0; i < length; i++) {
+        Constructor.resolve(entries[i]).then(resolve, reject);
+      }
+    });
+  }
+}