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											2021-05-05 10:13:49 -07:00
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							|  |  |  |  | id: bd7123c9c441eddfaeb5bdef | 
					
						
							|  |  |  |  | title: 理解布爾值 | 
					
						
							|  |  |  |  | challengeType: 1 | 
					
						
							|  |  |  |  | videoUrl: 'https://scrimba.com/c/c9Me8t4' | 
					
						
							|  |  |  |  | forumTopicId: 301176 | 
					
						
							|  |  |  |  | dashedName: understanding-boolean-values | 
					
						
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							|  |  |  |  | # --description--
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							|  |  |  |  | 另一種數據類型是布爾(<dfn>Boolean</dfn>)。 布爾值只能是兩個值中的一個:`true` 或者 `false`。 它非常像電路開關,`true` 是 “開”,`false` 是 “關”。 這兩種狀態是互斥的。 | 
					
						
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											2021-06-14 23:47:03 +09:00
										 |  |  |  | **注意:** 布爾值是不帶引號的。 字符串 `"true"` 和 `"false"` 不是布爾值,在 JavaScript 中也沒有特殊含義。 | 
					
						
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											2021-05-05 10:13:49 -07:00
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							|  |  |  |  | # --instructions--
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							|  |  |  |  | 修改 `welcomeToBooleans` 函數,當 run 按鈕點擊時讓它返回 `true` 而不是 `false`。 | 
					
						
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							|  |  |  |  | # --hints--
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							|  |  |  |  | `welcomeToBooleans()` 函數應該返回一個布爾值 (`true` 或者 `false`)。 | 
					
						
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | assert(typeof welcomeToBooleans() === 'boolean'); | 
					
						
							|  |  |  |  | ``` | 
					
						
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							|  |  |  |  | `welcomeToBooleans()` 應該返回 `true`。 | 
					
						
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | assert(welcomeToBooleans() === true); | 
					
						
							|  |  |  |  | ``` | 
					
						
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							|  |  |  |  | # --seed--
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							|  |  |  |  | ## --after-user-code--
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | welcomeToBooleans(); | 
					
						
							|  |  |  |  | ``` | 
					
						
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							|  |  |  |  | ## --seed-contents--
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | function welcomeToBooleans() { | 
					
						
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							|  |  |  |  |   // Only change code below this line | 
					
						
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							|  |  |  |  |   return false; // Change this line | 
					
						
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							|  |  |  |  |   // Only change code above this line | 
					
						
							|  |  |  |  | } | 
					
						
							|  |  |  |  | ``` | 
					
						
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							|  |  |  |  | # --solutions--
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							|  |  |  |  | ```js | 
					
						
							|  |  |  |  | function welcomeToBooleans() { | 
					
						
							|  |  |  |  |   return true; // Change this line | 
					
						
							|  |  |  |  | } | 
					
						
							|  |  |  |  | ``` |