0a895dad47
* Local scope and functions: Make the example less confusing * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/local-scope-and-functions.md Co-authored-by: Krzysztof G. <60067306+gikf@users.noreply.github.com> Co-authored-by: Krzysztof G. <60067306+gikf@users.noreply.github.com>
87 lines
2.0 KiB
Markdown
87 lines
2.0 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244bf
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title: Local Scope and Functions
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cd62NhM'
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forumTopicId: 18227
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dashedName: local-scope-and-functions
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---
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# --description--
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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.
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Here is a function `myTest` with a local variable called `loc`.
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```js
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function myTest() {
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const loc = "foo";
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console.log(loc);
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}
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myTest();
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console.log(loc);
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```
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The `myTest()` function call will display the string `foo` in the console. The `console.log(loc)` line (outside of the `myTest` function) will throw an error, as `loc` is not defined outside of the function.
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# --instructions--
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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.
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**Note:** The console will still display `ReferenceError: myVar is not defined`, but this will not cause the tests to fail.
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# --hints--
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The code should not contain a global `myVar` variable.
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```js
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function declared() {
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myVar;
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}
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assert.throws(declared, ReferenceError);
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```
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You should add a local `myVar` variable.
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```js
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assert(
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/functionmyLocalScope\(\)\{.*(var|let|const)myVar[\s\S]*}/.test(
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__helpers.removeWhiteSpace(code)
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)
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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 myLocalScope() {
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// Only change code below this line
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console.log('inside myLocalScope', myVar);
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}
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myLocalScope();
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// Run and check the console
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// myVar is not defined outside of myLocalScope
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console.log('outside myLocalScope', myVar);
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```
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# --solutions--
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```js
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function myLocalScope() {
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// Only change code below this line
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let myVar;
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console.log('inside myLocalScope', myVar);
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}
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myLocalScope();
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// Run and check the console
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// myVar is not defined outside of myLocalScope
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console.log('outside myLocalScope', myVar);
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```
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