100 lines
2.0 KiB
Markdown
100 lines
2.0 KiB
Markdown
---
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id: 5cdafbe72913098997531682
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title: Handle a Rejected Promise with catch
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challengeType: 1
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forumTopicId: 301204
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---
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# --description--
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`catch` is the method used when your promise has been rejected. It is executed immediately after a promise's `reject` method is called. Here’s the syntax:
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```js
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myPromise.catch(error => {
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// do something with the error.
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});
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```
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`error` is the argument passed in to the `reject` method.
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# --instructions--
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Add the `catch` method to your promise. Use `error` as the parameter of its callback function and log `error` to the console.
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# --hints--
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You should call the `catch` method on the promise.
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```js
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assert(
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__helpers.removeWhiteSpace(code).match(/(makeServerRequest|\))\.catch\(/g)
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);
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```
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Your `catch` method should have a callback function with `error` as its parameter.
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```js
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assert(errorIsParameter);
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```
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You should log `error` to the console.
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```js
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assert(
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errorIsParameter &&
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__helpers
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.removeWhiteSpace(code)
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.match(/\.catch\(.*?error.*?console.log\(error\).*?\)/)
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);
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```
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# --seed--
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## --after-user-code--
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```js
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const errorIsParameter = /\.catch\((function\(error\){|error|\(error\)=>)/.test(__helpers.removeWhiteSpace(code));
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```
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## --seed-contents--
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```js
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const makeServerRequest = new Promise((resolve, reject) => {
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// responseFromServer is set to false to represent an unsuccessful response from a server
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let responseFromServer = false;
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if(responseFromServer) {
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resolve("We got the data");
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} else {
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reject("Data not received");
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}
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});
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makeServerRequest.then(result => {
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console.log(result);
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});
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```
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# --solutions--
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```js
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const makeServerRequest = new Promise((resolve, reject) => {
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// responseFromServer is set to false to represent an unsuccessful response from a server
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let responseFromServer = false;
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if(responseFromServer) {
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resolve("We got the data");
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} else {
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reject("Data not received");
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}
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});
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makeServerRequest.then(result => {
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console.log(result);
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});
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makeServerRequest.catch(error => {
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console.log(error);
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});
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```
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