truthy
(真实的)。
换句话说,你将获得一个对象的数组集合。谓词pre
是一个对象的属性,如果它的值是truthy
(真实的) ,则返回true
,否则,返回false
。
JavaScript 中,如果一个值在 Boolean 的上下文中(比如if
语句)可以被执行为true
,那么这个值就被认为是truthy
的。
注意,你可以选择使用.
或[]
来访问对象属性对应的值。
truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex")
应该返回true
。'
testString: 'assert.strictEqual(truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex"), true);'
- text: 'truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex")
应该返回false
。'
testString: 'assert.strictEqual(truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex"), false);'
- text: 'truthCheck([{"user": "Tinky-Winky", "sex": "male", "age": 0}, {"user": "Dipsy", "sex": "male", "age": 3}, {"user": "Laa-Laa", "sex": "female", "age": 5}, {"user": "Po", "sex": "female", "age": 4}], "age")
应该返回false
。'
testString: 'assert.strictEqual(truthCheck([{"user": "Tinky-Winky", "sex": "male", "age": 2}, {"user": "Dipsy", "sex": "male", "age": 0}, {"user": "Laa-Laa", "sex": "female", "age": 5}, {"user": "Po", "sex": "female", "age": 4}], "age"), false);'
- text: 'truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true}, {"name": "FastFoward", "onBoat": null}], "onBoat")
应该返回false
。'
testString: 'assert.strictEqual(truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true}, {"name": "FastFoward", "onBoat": null}], "onBoat"), false);'
- text: 'truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true, "alias": "Repete"}, {"name": "FastFoward", "onBoat": true}], "onBoat")
应该返回true
。'
testString: 'assert.strictEqual(truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true, "alias": "Repete"}, {"name": "FastFoward", "onBoat": true}], "onBoat"), true);'
- text: 'truthCheck([{"single": "yes"}], "single")
应该返回true
。'
testString: 'assert.strictEqual(truthCheck([{"single": "yes"}], "single"), true);'
- text: 'truthCheck([{"single": ""}, {"single": "double"}], "single")
应该返回false
。'
testString: 'assert.strictEqual(truthCheck([{"single": ""}, {"single": "double"}], "single"), false);'
- text: 'truthCheck([{"single": "double"}, {"single": undefined}], "single")
应该返回false
。'
testString: 'assert.strictEqual(truthCheck([{"single": "double"}, {"single": undefined}], "single"), false);'
- text: 'truthCheck([{"single": "double"}, {"single": NaN}], "single")
应该返回false
。'
testString: 'assert.strictEqual(truthCheck([{"single": "double"}, {"single": NaN}], "single"), false);'
```