* 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>
87 lines
1.8 KiB
Markdown
87 lines
1.8 KiB
Markdown
---
|
|
id: 56533eb9ac21ba0edf2244bf
|
|
title: Local Scope and Functions
|
|
challengeType: 1
|
|
videoUrl: 'https://scrimba.com/c/cd62NhM'
|
|
forumTopicId: 18227
|
|
dashedName: local-scope-and-functions
|
|
---
|
|
|
|
# --description--
|
|
|
|
Variables which are declared within a function, as well as the function parameters have <dfn>local</dfn> scope. That means, they are only visible within that function.
|
|
|
|
Here is a function `myTest` with a local variable called `loc`.
|
|
|
|
```js
|
|
function myTest() {
|
|
var loc = "foo";
|
|
console.log(loc);
|
|
}
|
|
myTest(); // logs "foo"
|
|
console.log(loc); // loc is not defined
|
|
```
|
|
|
|
`loc` is not defined outside of the function.
|
|
|
|
# --instructions--
|
|
|
|
The editor has two `console.log`s to help you see what is happening. Check the console as you code to see how it changes. Declare a local variable `myVar` inside `myLocalScope` and run the tests.
|
|
|
|
**Note:** The console will still have 'ReferenceError: myVar is not defined', but this will not cause the tests to fail.
|
|
|
|
# --hints--
|
|
|
|
The code should not contain a global `myVar` variable.
|
|
|
|
```js
|
|
function declared() {
|
|
myVar;
|
|
}
|
|
assert.throws(declared, ReferenceError);
|
|
```
|
|
|
|
You should add a local `myVar` variable.
|
|
|
|
```js
|
|
assert(
|
|
/functionmyLocalScope\(\)\{.+(var|let|const)myVar[\s\S]*}/.test(
|
|
__helpers.removeWhiteSpace(code)
|
|
)
|
|
);
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --seed-contents--
|
|
|
|
```js
|
|
function myLocalScope() {
|
|
|
|
// Only change code below this line
|
|
|
|
console.log('inside myLocalScope', myVar);
|
|
}
|
|
myLocalScope();
|
|
|
|
// Run and check the console
|
|
// myVar is not defined outside of myLocalScope
|
|
console.log('outside myLocalScope', myVar);
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```js
|
|
function myLocalScope() {
|
|
|
|
// Only change code below this line
|
|
var myVar;
|
|
console.log('inside myLocalScope', myVar);
|
|
}
|
|
myLocalScope();
|
|
|
|
// Run and check the console
|
|
// myVar is not defined outside of myLocalScope
|
|
console.log('outside myLocalScope', myVar);
|
|
```
|