JavaScript

✦ PRO

Type real JavaScript: ES6 syntax and built-ins, then variables, functions, arrays, objects, classes, promises and the DOM.

ES6 declarations and statements

let and const, arrow functions, generators, classes, for...of, export and import.

Variables
Arrows
Generators
Class
for...of
Export
Import

ES6 expressions

Default, rest and destructured parameters, spread and destructuring declarations.

Default parameters
Rest parameters
Destructuring parameters
Spread
Destructuring declarations

ES6 built-ins

Promise, Map, Set, WeakMap, WeakSet and the new Array methods.

Promise
Map
Set
WeakMap
WeakSet
Array

Variables

Practice let, const, and var declarations with different data types.

Declare variables with const, let, and var
Constants, counters, and empty array initialization
Arithmetic with variables
Destructuring assignments for arrays and objects

Functions

Type function declarations, arrow functions, and default parameters.

A basic function declaration with template literal
Arrow functions with implicit return
Function with default parameter and shorthand object
Arrow function with block body
Higher-order function composition

Strings & Template Literals

Practice string methods and template literal expressions.

Template literals with embedded expressions
Common string methods
Splitting, joining, and searching strings
Multi-line template literal with method calls

Arrays & Array Methods

Type array creation and common functional array methods.

Array creation with push and pop
Map and filter with arrow functions
Reduce and find methods
Sorting with spread copy and flattening
Deduplication with Set and array slicing

Objects & Destructuring

Practice object literals, destructuring, and spread syntax.

Object literal with multiple properties
Object destructuring with rest and renaming
Object spread for merging and updating
Static Object methods for keys, values, and entries

Conditionals

Type if/else blocks, ternary operators, and switch statements.

Basic if/else if conditional block
Ternary operator for inline conditionals
Switch statement with return values
Nullish coalescing and optional chaining

Loops

Practice for loops, while loops, and iteration methods.

Classic for loop with index
for...of loops for arrays and maps
While loop with break condition
forEach with index and template literal
Method chaining with filter and map

Classes & Prototypes

Type ES6 class syntax with constructors, methods, and inheritance.

Basic class with constructor
Class inheritance with extends
Private fields and getter methods
Class using Map for event listeners

Promises & Async/Await

Practice asynchronous patterns with promises, async/await, and error handling.

Basic fetch with await
Async function with try/catch error handling
Parallel requests with Promise.all and destructuring
Creating a new Promise with resolve and reject

DOM Manipulation

Type common DOM API calls for selecting, creating, and modifying elements.

Selecting elements by ID and query selector
Creating and appending a new element
Adding a click event listener
Modifying styles and class lists
Working with element attributes

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