Update js codes.docx

Author: priya42bagde

js codes.docx

@@ -2395,3 +2395,19 @@ let promises = [
 
 Promise.allSettled(promises).then((result) => console.log(result));
 =======================================================================================================================================================================
+Polyfill of race:
+Promise.letsBuildARace = function(arrayOfPromises){
+return new Promise((resolve, reject) => {
+arrayOfPromises.forEach((promise) => {
+Promise.resolve(promise).then(resolve, reject);
+})
+})
+}
+For Example:
+var a = new Promise((resolve) => setTimeout(()=>{resolve(3)},200));
+var b = new Promise((resolve,reject)=>reject(9));
+var c= new Promise((resolve) => resolve(5));
+
+var d= Promise.letsBuildARace([a,b,c]);
+d.then(result=>console.log(result))
+=========================================================================================================================================================================