wehub-resource-sync
dde272c4b8
i18n - Build Validation / Validate i18n Builds (24) (push) Has been cancelled
CI - Node.js / Lint (24) (push) Has been cancelled
CI - Node.js / Build (24) (push) Has been cancelled
CI - Node.js / Test (24) (push) Has been cancelled
CI - Node.js / Test - Upcoming Changes (24) (push) Has been cancelled
CI - Node.js / Test - i18n (italian, 24) (push) Has been cancelled
CI - Node.js / Test - i18n (portuguese, 24) (push) Has been cancelled
CD - Docker - GHCR Images / Build and Push Images (push) Has been cancelled
292 lines
3.8 KiB
Markdown
292 lines
3.8 KiB
Markdown
---
|
|
id: 66edd4f31ff19bf5573bf64b
|
|
title: JavaScript Functional Programming Quiz
|
|
challengeType: 8
|
|
dashedName: quiz-javascript-functional-programming
|
|
---
|
|
|
|
# --description--
|
|
|
|
To pass the quiz, you must correctly answer at least 9 of the 10 questions below.
|
|
|
|
# --quizzes--
|
|
|
|
## --quiz--
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
What is a pure function?
|
|
|
|
#### --distractors--
|
|
|
|
A function that modifies global variables and returns either `undefined` or `null`.
|
|
|
|
---
|
|
|
|
A function that logs an output to the console.
|
|
|
|
---
|
|
|
|
A function that changes its behavior based on external factors and returns `null`.
|
|
|
|
#### --answer--
|
|
|
|
A function that always returns the same output for the same input and produces no side effects.
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
What is a side effect in functional programming?
|
|
|
|
#### --distractors--
|
|
|
|
An unexpected `TypeError` in your code.
|
|
|
|
---
|
|
|
|
A function that takes too long to execute and crashes the program.
|
|
|
|
---
|
|
|
|
A recursive function call that produces an infinite loop and crashes the program.
|
|
|
|
#### --answer--
|
|
|
|
A change to the state of the program that are observable outside the function.
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
What is currying in functional programming?
|
|
|
|
#### --distractors--
|
|
|
|
A technique for designing tests to help you ensure your code is 100% error free.
|
|
|
|
---
|
|
|
|
A more optimized way to write recursive functions so they run twice as fast as other functions.
|
|
|
|
---
|
|
|
|
The process of building, designing and testing your code to ensure that it meets the standards laid out by ECMAScript.
|
|
|
|
#### --answer--
|
|
|
|
The process of transforming a function with multiple arguments into a sequence of functions, each with a single argument.
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
What will be the output for the following pure function?
|
|
|
|
```js
|
|
const add = (a, b) => a + b;
|
|
console.log(add(2, 5));
|
|
```
|
|
|
|
#### --distractors--
|
|
|
|
`3`
|
|
|
|
---
|
|
|
|
`4`
|
|
|
|
---
|
|
|
|
`undefined`
|
|
|
|
#### --answer--
|
|
|
|
`7`
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
Which of the following is an example of currying?
|
|
|
|
#### --distractors--
|
|
|
|
```js
|
|
const curriedAverage = (a, b, c) => a + b + c / 3
|
|
```
|
|
|
|
---
|
|
|
|
```js
|
|
const curriedAverage = (a, b, c) => a + b + c
|
|
```
|
|
|
|
---
|
|
|
|
```js
|
|
function curriedAverage(a) {
|
|
return a
|
|
}
|
|
|
|
function curried(c) {
|
|
return c
|
|
}
|
|
```
|
|
|
|
#### --answer--
|
|
|
|
```js
|
|
function curriedAverage(a) {
|
|
return function(b) {
|
|
return function(c) {
|
|
return (a + b + c) / 3;
|
|
};
|
|
};
|
|
}
|
|
```
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
Which of the following is a key principle of functional programming?
|
|
|
|
#### --distractors--
|
|
|
|
Modifying global variables frequently.
|
|
|
|
---
|
|
|
|
Using mutable data structures extensively.
|
|
|
|
---
|
|
|
|
Emphasizing object-oriented inheritance.
|
|
|
|
#### --answer--
|
|
|
|
Avoiding side effects and using immutable data.
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
What is an impure function?
|
|
|
|
#### --distractors--
|
|
|
|
A function that returns an object.
|
|
|
|
---
|
|
|
|
A function without side effects.
|
|
|
|
---
|
|
|
|
A function that returns `null`
|
|
|
|
#### --answer--
|
|
|
|
A function with side effects.
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
Which of the following is the correct way to call a curried function?
|
|
|
|
#### --distractors--
|
|
|
|
```js
|
|
curriedAverage(2 3 4);
|
|
```
|
|
|
|
---
|
|
|
|
```js
|
|
curriedAverage(2)==(3)==(4);
|
|
```
|
|
|
|
---
|
|
|
|
```js
|
|
curriedAverage(2)=>(3)=>(4);
|
|
```
|
|
|
|
#### --answer--
|
|
|
|
```js
|
|
curriedAverage(2)(3)(4);
|
|
```
|
|
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
Which of the following is an example of an impure function?
|
|
|
|
#### --distractors--
|
|
|
|
```js
|
|
function example(num) {
|
|
return num;
|
|
}
|
|
```
|
|
|
|
---
|
|
|
|
```js
|
|
function sum(num1, num2) {
|
|
return num1 + num2
|
|
}
|
|
```
|
|
|
|
---
|
|
|
|
```js
|
|
function addToTotal(value) {
|
|
let total = 0;
|
|
total += value;
|
|
return total;
|
|
}
|
|
```
|
|
|
|
#### --answer--
|
|
|
|
```js
|
|
let total = 0;
|
|
function addToTotal(value) {
|
|
total += value;
|
|
return total;
|
|
}
|
|
```
|
|
|
|
### --question--
|
|
|
|
#### --text--
|
|
|
|
Which of the following is NOT an example of a side effect?
|
|
|
|
#### --distractors--
|
|
|
|
Writing to a file.
|
|
|
|
---
|
|
|
|
Modifying a global variable.
|
|
|
|
---
|
|
|
|
Making an API call.
|
|
|
|
#### --answer--
|
|
|
|
Returning the sum of two values.
|
|
|
|
|
|
|