5.0 KiB
id, title, challengeType, forumTopicId, dashedName
id | title | challengeType | forumTopicId | dashedName |
---|---|---|---|---|
a10d2431ad0c6a099a4b8b52 | 一切都是True | 5 | 16011 | everything-be-true |
--description--
檢查謂詞(第二個參數)在集合(第一個參數)的所有元素是否爲 truthy。
換句話說,你將獲得一個對象的數組集合。 如果數組中的每個對象裏,pre
對應屬性值均爲 truthy
,則返回 true
。 否則,返回 false
。
JavaScript 中,如果一個值在 Boolean 的上下文中的執行結果爲 true
,那麼我們稱這個值是 truthy
的。
別忘了,你可以使用點號表示法或方括號表示法([]
)來訪問對象的屬性。
--hints--
truthCheck([{name: "Quincy", role: "Founder", isBot: false}, {name: "Naomi", role: "", isBot: false}, {name: "Camperbot", role: "Bot", isBot: true}], "isBot")
應該返回 false
。
assert.strictEqual(truthCheck(
[
{ name: "Quincy", role: "Founder", isBot: false },
{ name: "Naomi", role: "", isBot: false },
{ name: "Camperbot", role: "Bot", isBot: true }
],
"isBot"), false);
truthCheck([{name: "Quincy", role: "Founder", isBot: false}, {name: "Naomi", role: "", isBot: false}, {name: "Camperbot", role: "Bot", isBot: true}], "name")
應該返回 true
。
assert.strictEqual(truthCheck(
[
{ name: "Quincy", role: "Founder", isBot: false },
{ name: "Naomi", role: "", isBot: false },
{ name: "Camperbot", role: "Bot", isBot: true }
],
"name"), true);
truthCheck([{name: "Quincy", role: "Founder", isBot: false}, {name: "Naomi", role: "", isBot: false}, {name: "Camperbot", role: "Bot", isBot: true}], "role")
應該返回 false
。
assert.strictEqual(truthCheck(
[
{ name: "Quincy", role: "Founder", isBot: false },
{ name: "Naomi", role: "", isBot: false },
{ name: "Camperbot", role: "Bot", isBot: true }
],
"role"), false);
truthCheck([{name: "Pikachu", number: 25, caught: 3}, {name: "Togepi", number: 175, caught: 1}], "number")
應該返回 true
。
assert.strictEqual(truthCheck(
[
{ name: "Pikachu", number: 25, caught: 3 },
{ name: "Togepi", number: 175, caught: 1 },
],
"number"), true);
truthCheck([{name: "Pikachu", number: 25, caught: 3}, {name: "Togepi", number: 175, caught: 1}, {name: "MissingNo", number: NaN, caught: 0}], "caught")
應該返回 false
。
assert.strictEqual(truthCheck(
[
{ name: "Pikachu", number: 25, caught: 3 },
{ name: "Togepi", number: 175, caught: 1 },
{ name: "MissingNo", number: NaN, caught: 0 },
],
"caught"), false);
truthCheck([{name: "Pikachu", number: 25, caught: 3}, {name: "Togepi", number: 175, caught: 1}, {name: "MissingNo", number: NaN, caught: 0}], "number")
應該返回 false
。
assert.strictEqual(truthCheck(
[
{ name: "Pikachu", number: 25, caught: 3 },
{ name: "Togepi", number: 175, caught: 1 },
{ name: "MissingNo", number: NaN, caught: 0 },
],
"number"), false);
truthCheck([{name: "Quincy", username: "QuincyLarson"}, {name: "Naomi", username: "nhcarrigan"}, {name: "Camperbot"}], "username")
應該返回 false
。
assert.strictEqual(truthCheck(
[
{ name: "Quincy", username: "QuincyLarson" },
{ name: "Naomi", username: "nhcarrigan" },
{ name: "Camperbot" }
],
"username"), false);
truthCheck([{name: "freeCodeCamp", users: [{name: "Quincy"}, {name: "Naomi"}]}, {name: "Code Radio", users: [{name: "Camperbot"}]}, {name: "", users: []}], "users")
應該返回 true
。
assert.strictEqual(truthCheck(
[
{ name: "freeCodeCamp", users: [{ name: "Quincy" }, { name: "Naomi" }] },
{ name: "Code Radio", users: [{ name: "Camperbot" }] },
{ name: "", users: [] },
],
"users"), true);
truthCheck([{id: 1, data: {url: "https://freecodecamp.org", name: "freeCodeCamp"}}, {id: 2, data: {url: "https://coderadio.freecodecamp.org/", name: "CodeRadio"}}, {id: null, data: {}}], "data")
應該返回 true
。
assert.strictEqual(truthCheck(
[
{ id: 1, data: { url: "https://www.freecodecamp.org", name: "freeCodeCamp" } },
{ id: 2, data: { url: "https://coderadio.freecodecamp.org/", name: "CodeRadio" } },
{ id: null, data: {} },
],
"data"), true);
truthCheck([{id: 1, data: {url: "https://freecodecamp.org", name: "freeCodeCamp"}}, {id: 2, data: {url: "https://coderadio.freecodecamp.org/", name: "CodeRadio"}}, {id: null, data: {}}], "id")
應該返回 false
。
assert.strictEqual(truthCheck(
[
{ id: 1, data: { url: "https://www.freecodecamp.org", name: "freeCodeCamp" } },
{ id: 2, data: { url: "https://coderadio.freecodecamp.org/", name: "CodeRadio" } },
{ id: null, data: {} },
],
"id"), false);
--seed--
--seed-contents--
function truthCheck(collection, pre) {
return pre;
}
truthCheck([{name: "Quincy", role: "Founder", isBot: false}, {name: "Naomi", role: "", isBot: false}, {name: "Camperbot", role: "Bot", isBot: true}], "isBot");
--solutions--
function truthCheck(collection, pre) {
return collection.every(function(e) { return e[pre]; });
}