ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
71 lines
1.5 KiB
Markdown
71 lines
1.5 KiB
Markdown
---
|
|
id: 56533eb9ac21ba0edf2244ba
|
|
title: Understand String Immutability
|
|
challengeType: 1
|
|
videoUrl: 'https://scrimba.com/c/cWPVaUR'
|
|
forumTopicId: 18331
|
|
dashedName: understand-string-immutability
|
|
---
|
|
|
|
# --description--
|
|
|
|
In JavaScript, `String` values are <dfn>immutable</dfn>, which means that they cannot be altered once created.
|
|
|
|
For example, the following code:
|
|
|
|
```js
|
|
var myStr = "Bob";
|
|
myStr[0] = "J";
|
|
```
|
|
|
|
cannot change the value of `myStr` to "Job", because the contents of `myStr` cannot be altered. Note that this does *not* mean that `myStr` cannot be changed, just that the individual characters of a <dfn>string literal</dfn> cannot be changed. The only way to change `myStr` would be to assign it with a new string, like this:
|
|
|
|
```js
|
|
var myStr = "Bob";
|
|
myStr = "Job";
|
|
```
|
|
|
|
# --instructions--
|
|
|
|
Correct the assignment to `myStr` so it contains the string value of `Hello World` using the approach shown in the example above.
|
|
|
|
# --hints--
|
|
|
|
`myStr` should have a value of `Hello World`.
|
|
|
|
```js
|
|
assert(myStr === 'Hello World');
|
|
```
|
|
|
|
You should not change the code above the specified comment.
|
|
|
|
```js
|
|
assert(/myStr = "Jello World"/.test(code));
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --after-user-code--
|
|
|
|
```js
|
|
(function(v){return "myStr = " + v;})(myStr);
|
|
```
|
|
|
|
## --seed-contents--
|
|
|
|
```js
|
|
// Setup
|
|
var myStr = "Jello World";
|
|
|
|
// Only change code below this line
|
|
myStr[0] = "H"; // Change this line
|
|
// Only change code above this line
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```js
|
|
var myStr = "Jello World";
|
|
myStr = "Hello World";
|
|
```
|