59 lines
1.1 KiB
Markdown
59 lines
1.1 KiB
Markdown
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---
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id: a6e40f1041b06c996f7b2406
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title: Finders Keepers
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challengeType: 5
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forumTopicId: 16016
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dashedName: finders-keepers
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---
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# --description--
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Create a function that looks through an array `arr` and returns the first element in it that passes a 'truth test'. This means that given an element `x`, the 'truth test' is passed if `func(x)` is `true`. If no element passes the test, return `undefined`.
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# --hints--
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`findElement([1, 3, 5, 8, 9, 10], function(num) { return num % 2 === 0; })` should return 8.
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```js
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assert.strictEqual(
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findElement([1, 3, 5, 8, 9, 10], function (num) {
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return num % 2 === 0;
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}),
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8
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);
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```
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`findElement([1, 3, 5, 9], function(num) { return num % 2 === 0; })` should return undefined.
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```js
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assert.strictEqual(
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findElement([1, 3, 5, 9], function (num) {
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return num % 2 === 0;
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}),
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undefined
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);
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```
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# --seed--
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## --seed-contents--
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```js
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function findElement(arr, func) {
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let num = 0;
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return num;
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}
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findElement([1, 2, 3, 4], num => num % 2 === 0);
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```
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# --solutions--
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```js
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function findElement(arr, func) {
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return arr.filter(func)[0];
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}
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findElement([1, 2, 3, 4], num => num % 2 === 0);
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```
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