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* Clarify understand-string-immutability Remove some misleading explanation (immutability is orthogonal to literals). * Remove extraneous whitespace Co-authored-by: Jeremy L Thompson <jeremy@jeremylt.org> * Improve explanation per review suggestion Co-authored-by: Jeremy L Thompson <jeremy@jeremylt.org> Co-authored-by: Jeremy L Thompson <jeremy@jeremylt.org>
71 lines
1.4 KiB
Markdown
71 lines
1.4 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244ba
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title: Understand String Immutability
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cWPVaUR'
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forumTopicId: 18331
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dashedName: understand-string-immutability
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---
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# --description--
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In JavaScript, `String` values are <dfn>immutable</dfn>, which means that they cannot be altered once created.
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For example, the following code will produce an error because the letter `B` in the string `Bob` cannot be changed to the letter `J`:
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```js
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let myStr = "Bob";
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myStr[0] = "J";
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```
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Note that this does *not* mean that `myStr` could not be re-assigned. The only way to change `myStr` would be to assign it with a new value, like this:
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```js
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let myStr = "Bob";
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myStr = "Job";
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```
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# --instructions--
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Correct the assignment to `myStr` so it contains the string value of `Hello World` using the approach shown in the example above.
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# --hints--
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`myStr` should have a value of the string `Hello World`.
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```js
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assert(myStr === 'Hello World');
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```
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You should not change the code above the specified comment.
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```js
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assert(/myStr = "Jello World"/.test(code));
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```
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# --seed--
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## --after-user-code--
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```js
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(function(v){return "myStr = " + v;})(myStr);
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```
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## --seed-contents--
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```js
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// Setup
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let myStr = "Jello World";
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// Only change code below this line
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myStr[0] = "H"; // Change this line
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// Only change code above this line
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```
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# --solutions--
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```js
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let myStr = "Jello World";
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myStr = "Hello World";
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```
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