ES6

Question 1

What are the three states a Promise can be in?

Answer 1

pending: initial state, neither fulfilled nor rejected.

fulfilled: meaning that the operation was completed successfully.

rejected: meaning that the operation failed.

Question 2

How do you handle the fulfillment of a Promise?

Answer 2

You call .then( ) on a Promise and then you pass in a callback that expects up to one parameter, the value it results to and then that will tell it what to do

Question 3

How do you handle the rejection of a Promise?

Question 4

What is “syntactic sugar”?

Answer 4

In computer science, syntactic sugar is syntax within a programming language that is designed to make things easier to read or to express. It makes the language “sweeter” for human use: things can be expressed more clearly, more concisely, or in an alternative style that some may prefer. Syntactic sugar is usually a shorthand for a common operation that could also be expressed in an alternate, more verbose, form: The programmer has a choice of whether to use the shorter form or the longer form, but will usually use the shorter form since it is shorter and easier to type and read.

Question 5

What is the typeof an ES6 class?

Answer 5

function

Question 6

Describe ES6 class syntax.

Answer 6

class Person {
constructor(name) {
this.name = name;
}
getName( ) {
return this.name;
}
}

Question 7

What is “refactoring”?

Answer 7

code refactoring is the process of restructuring existing computer code—changing the factoring—without changing its external behavior. Refactoring is intended to improve the design, structure, and/or implementation of the software (its non-functional attributes), while preserving its functionality. Potential advantages of refactoring may include improved code readability and reduced complexity; these can improve the source code’s maintainability and create a simpler, cleaner, or more expressive internal architecture or object model to improve extensibility. Another potential goal for refactoring is improved performance; software engineers face an ongoing challenge to write programs that perform faster or use less memory.

Question 8

How are ES Modules different from CommonJS modules?

Answer 8

Different syntax

CommonJS modules load using require(), and variables and functions export from a CommonJS module with module.exports.

ES Modules load using import & export statements

Question 9

What kind of modules can Webpack support?

Answer 9

Natively supports:
- ECMAScript modules
- CommonJS modules
- AMD modules
- Assets
- WebAssembly modules