freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../es6/handle-a-fulfilled-promise-...

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id title challengeType forumTopicId dashedName
5cdafbd72913098997531681 Handle a Fulfilled Promise with then 1 301203 handle-a-fulfilled-promise-with-then

--description--

Promises are most useful when you have a process that takes an unknown amount of time in your code (i.e. something asynchronous), often a server request. When you make a server request it takes some amount of time, and after it completes you usually want to do something with the response from the server. This can be achieved by using the then method. The then method is executed immediately after your promise is fulfilled with resolve. Heres an example:

myPromise.then(result => {
  // do something with the result.
});

result comes from the argument given to the resolve method.

--instructions--

Add the then method to your promise. Use result as the parameter of its callback function and log result to the console.

--hints--

You should call the then method on the promise.

assert(
  __helpers.removeWhiteSpace(code).match(/(makeServerRequest|\))\.then\(/g)
);

Your then method should have a callback function with result as its parameter.

assert(resultIsParameter);

You should log result to the console.

assert(
  resultIsParameter &&
    __helpers
      .removeWhiteSpace(code)
      .match(/\.then\(.*?result.*?console.log\(result\).*?\)/)
);

--seed--

--after-user-code--

const resultIsParameter = /\.then\((function\(result\){|result|\(result\)=>)/.test(__helpers.removeWhiteSpace(code));

--seed-contents--

const makeServerRequest = new Promise((resolve, reject) => {
  // responseFromServer is set to true to represent a successful response from a server
  let responseFromServer = true;
    
  if(responseFromServer) {
    resolve("We got the data");
  } else {  
    reject("Data not received");
  }
});

--solutions--

const makeServerRequest = new Promise((resolve, reject) => {
  // responseFromServer is set to true to represent a successful response from a server
  let responseFromServer = true;
    
  if(responseFromServer) {
    resolve("We got the data");
  } else {  
    reject("Data not received");
  }
});

makeServerRequest.then(result => {
  console.log(result);
});