5.0 KiB
5.0 KiB
id | title | isRequired | challengeType | forumTopicId | localeTitle |
---|---|---|---|---|---|
a10d2431ad0c6a099a4b8b52 | Everything Be True | true | 5 | 16011 | Все верно |
Description
pre
будет свойством объекта, и вам нужно вернуть true
если его значение является truthy
. В противном случае верните false
. В JavaScript truthy
значениями являются значения, которые переводятся в true
при оценке в булевом контексте. Помните, что вы можете получить доступ к свойствам объекта с помощью либо точечной нотации, либо обозначения []
. Не забудьте использовать Read-Search-Ask, если вы застряли. Попробуйте подключить программу. Напишите свой собственный код.
Instructions
Tests
tests:
- text: '<code>truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex")</code> should return 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: '<code>truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex")</code> should return false.'
testString: 'assert.strictEqual(truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex"), false);'
- text: '<code>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")</code> should return 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: '<code>truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true}, {"name": "FastFoward", "onBoat": null}], "onBoat")</code> should return false'
testString: 'assert.strictEqual(truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true}, {"name": "FastFoward", "onBoat": null}], "onBoat"), false);'
- text: '<code>truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true, "alias": "Repete"}, {"name": "FastFoward", "onBoat": true}], "onBoat")</code> should return true'
testString: 'assert.strictEqual(truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true, "alias": "Repete"}, {"name": "FastFoward", "onBoat": true}], "onBoat"), true);'
- text: '<code>truthCheck([{"single": "yes"}], "single")</code> should return true'
testString: 'assert.strictEqual(truthCheck([{"single": "yes"}], "single"), true);'
- text: '<code>truthCheck([{"single": ""}, {"single": "double"}], "single")</code> should return false'
testString: 'assert.strictEqual(truthCheck([{"single": ""}, {"single": "double"}], "single"), false);'
- text: '<code>truthCheck([{"single": "double"}, {"single": undefined}], "single")</code> should return false'
testString: 'assert.strictEqual(truthCheck([{"single": "double"}, {"single": undefined}], "single"), false);'
- text: '<code>truthCheck([{"single": "double"}, {"single": NaN}], "single")</code> should return false'
testString: 'assert.strictEqual(truthCheck([{"single": "double"}, {"single": NaN}], "single"), false);'
Challenge Seed
function truthCheck(collection, pre) {
// Is everyone being true?
return pre;
}
truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex");
Solution
function truthCheck(collection, pre) {
// Does everyone have one of these?
return collection.every(function(e) { return e[pre]; });
}