2018-09-30 23:01:58 +01:00
										 
									 
								 
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								---
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								id: 587d7b8b367417b2b2512b50
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								title: Write Concise Declarative Functions with ES6
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								challengeType: 1
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											2019-08-05 09:17:33 -07:00
										 
									 
								 
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								forumTopicId: 301224
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											2021-01-13 03:31:00 +01:00
										 
									 
								 
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								dashedName: write-concise-declarative-functions-with-es6
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											2018-09-30 23:01:58 +01:00
										 
									 
								 
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								---
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								# --description--
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								When defining functions within objects in ES5, we have to use the keyword `function` as follows:
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								```js
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								const person = {
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								  name: "Taylor",
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								  sayHello: function() {
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								    return `Hello! My name is ${this.name}.`;
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								  }
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								};
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								```
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								With ES6, You can remove the `function` keyword and colon altogether when defining functions in objects. Here's an example of this syntax:
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								```js
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								const person = {
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								  name: "Taylor",
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								  sayHello() {
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								    return `Hello! My name is ${this.name}.`;
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								  }
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								};
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								```
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								# --instructions--
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								Refactor the function `setGear` inside the object `bicycle` to use the shorthand syntax described above.
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								# --hints--
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								Traditional function expression should not be used.
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											2020-11-27 19:02:05 +01:00
										 
									 
								 
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								```js
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								(getUserInput) => assert(!__helpers.removeJSComments(code).match(/function/));
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								```
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								`setGear` should be a declarative function.
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								```js
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								assert(
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								  typeof bicycle.setGear === 'function' && code.match(/setGear\s*\(.+\)\s*\{/)
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								);
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								```
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								`bicycle.setGear(48)` should change the `gear` value to 48.
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								```js
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								assert(new bicycle.setGear(48).gear === 48);
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								```
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								# --seed--
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								## --seed-contents--
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								```js
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								// Only change code below this line
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								const bicycle = {
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								  gear: 2,
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								  setGear: function(newGear) {
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								    this.gear = newGear;
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								  }
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								};
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								// Only change code above this line
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								bicycle.setGear(3);
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								console.log(bicycle.gear);
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								```
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								# --solutions--
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								```js
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								const bicycle = {
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								  gear: 2,
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								  setGear(newGear) {
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								    this.gear = newGear;
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								  }
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								};
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								bicycle.setGear(3);
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								```
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