* chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
72 lines
1.7 KiB
Markdown
72 lines
1.7 KiB
Markdown
---
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id: 587d7b89367417b2b2512b4b
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title: Use Destructuring Assignment to Assign Variables from Arrays
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challengeType: 1
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forumTopicId: 301213
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dashedName: use-destructuring-assignment-to-assign-variables-from-arrays
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---
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# --description--
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ES6 makes destructuring arrays as easy as destructuring objects.
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One key difference between the spread operator and array destructuring is that the spread operator unpacks all contents of an array into a comma-separated list. Consequently, you cannot pick or choose which elements you want to assign to variables.
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Destructuring an array lets us do exactly that:
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```js
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const [a, b] = [1, 2, 3, 4, 5, 6];
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console.log(a, b);
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```
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The console will display the values of `a` and `b` as `1, 2`.
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The variable `a` is assigned the first value of the array, and `b` is assigned the second value of the array. We can also access the value at any index in an array with destructuring by using commas to reach the desired index:
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```js
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const [a, b,,, c] = [1, 2, 3, 4, 5, 6];
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console.log(a, b, c);
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```
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The console will display the values of `a`, `b`, and `c` as `1, 2, 5`.
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# --instructions--
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Use destructuring assignment to swap the values of `a` and `b` so that `a` receives the value stored in `b`, and `b` receives the value stored in `a`.
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# --hints--
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The value of `a` should be `6`, after swapping.
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```js
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assert(a === 6);
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```
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The value of `b` should be `8`, after swapping.
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```js
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assert(b === 8);
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```
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You should use array destructuring to swap `a` and `b`.
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```js
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assert(/\[\s*(\w)\s*,\s*(\w)\s*\]\s*=\s*\[\s*\2\s*,\s*\1\s*\]/g.test(code));
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```
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# --seed--
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## --seed-contents--
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```js
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let a = 8, b = 6;
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// Only change code below this line
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```
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# --solutions--
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```js
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let a = 8, b = 6;
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[a, b] = [b, a];
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```
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