ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
112 lines
2.1 KiB
Markdown
112 lines
2.1 KiB
Markdown
---
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id: 587d7b7d367417b2b2512b1e
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title: Generate an Array of All Object Keys with Object.keys()
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challengeType: 1
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forumTopicId: 301160
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dashedName: generate-an-array-of-all-object-keys-with-object-keys
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---
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# --description--
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We can also generate an array which contains all the keys stored in an object using the `Object.keys()` method and passing in an object as the argument. This will return an array with strings representing each property in the object. Again, there will be no specific order to the entries in the array.
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# --instructions--
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Finish writing the `getArrayOfUsers` function so that it returns an array containing all the properties in the object it receives as an argument.
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# --hints--
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The `users` object should only contain the keys `Alan`, `Jeff`, `Sarah`, and `Ryan`
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```js
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assert(
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'Alan' in users &&
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'Jeff' in users &&
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'Sarah' in users &&
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'Ryan' in users &&
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Object.keys(users).length === 4
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);
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```
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The `getArrayOfUsers` function should return an array which contains all the keys in the `users` object
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```js
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assert(
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(function () {
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users.Sam = {};
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users.Lewis = {};
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let R = getArrayOfUsers(users);
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return (
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R.indexOf('Alan') !== -1 &&
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R.indexOf('Jeff') !== -1 &&
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R.indexOf('Sarah') !== -1 &&
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R.indexOf('Ryan') !== -1 &&
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R.indexOf('Sam') !== -1 &&
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R.indexOf('Lewis') !== -1
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);
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})() === true
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);
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```
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# --seed--
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## --seed-contents--
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```js
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let users = {
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Alan: {
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age: 27,
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online: false
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},
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Jeff: {
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age: 32,
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online: true
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},
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Sarah: {
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age: 48,
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online: false
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},
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Ryan: {
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age: 19,
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online: true
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}
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};
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function getArrayOfUsers(obj) {
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// Only change code below this line
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// Only change code above this line
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}
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console.log(getArrayOfUsers(users));
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```
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# --solutions--
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```js
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let users = {
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Alan: {
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age: 27,
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online: false
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},
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Jeff: {
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age: 32,
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online: true
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},
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Sarah: {
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age: 48,
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online: false
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},
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Ryan: {
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age: 19,
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online: true
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}
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};
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function getArrayOfUsers(obj) {
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return Object.keys(obj);
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}
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console.log(getArrayOfUsers(users));
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```
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