JavaScript - How is JS Dynamically Typed ?

JavaScript - How is JS Dynamically Typed ?

Last Updated : 15 Nov, 2024

Writing a data type (like we do in C/C++/Java) is not required

A variable name can hold any type of information

Mainly data type is stored with value (not with variable name) and is decided & checked at run time

JavaScript

let x = 42;   
console.log(x)

x = "hello";  
console.log(x)

x = [1, 2, 3]
console.log(x)

Output

42
hello
[ 1, 2, 3 ]

Type coercion happens automatically

JavaScript

let x = 5 + "5";
console.log(x);

Output

A function can receive any type of argument.

JavaScript

function print(x) {
  console.log(x);
}

print(42);        
print("hello");   
print({ key: "val" });

Output

42
hello
{ key: 'val' }

Note that dynamically typed languages are easier to program, but slower. TypeScript is a variation of JavaScript that is statically typed.

JavaScript - How is JS Dynamically Typed ?

kartik

Improve

Article Tags :

Similar Reads

How to Use Dynamic Variable Names in JavaScript?

Dynamic variable names are variable names that are not predefined but are generated dynamically during the execution of a program. This means the name of a variable can be determined at runtime, rather than being explicitly written in the code.Here are different ways to use dynamic variables in Java

How Dynamic Arrays Work in JavaScript ?

A dynamic array, also known as a resizable array or a dynamic array list, is a data structure that allows its size to be changed dynamically during program execution. Unlike static arrays, which have a fixed size determined at the time of declaration, dynamic arrays can grow or shrink in size as nee

Dynamic User Interfaces in JavaScript

User interfaces (UIs) have evolved from static layouts to dynamic and interactive experiences and JavaScript is a versatile and powerful programming language that plays a significant role in creating dynamic UIs that respond to user actions in real-time. Below are the methods to create a dynamic use

How to Create Dynamic Values and Objects in JavaScript?

In JavaScript, you can choose dynamic values or variable names and object names and choose to edit the variable name in the future without accessing the array, Dynamic values and objects in JavaScript allow changing, accessing, or creating values and object properties at runtime for flexibility and

How are characters stored in JavaScript ?

In many languages like C, C++, Java, etc. char is a primitive data type but in JavaScript, there is no special data type to store characters. Internally JavaScript stores characters as String only. In JavaScript, a String of length only is considered a character. Since a character is also a string s

JavaScript Data Types

In JavaScript, each value has a data type, defining its nature (e.g., Number, String, Boolean) and operations. Data types are categorized into Primitive (e.g., String, Number) and Non-Primitive (e.g., Objects, Arrays).Primitive Data Type1. NumberThe Number data type in JavaScript includes both integ

JavaScript Type Conversion

In JavaScript Type Conversion can be defined as converting the data type of the variables from one type to the other manually by the programmer(explicitly) or automatically by the JavaScript(implicitly).Implicit Type Conversion (Coercion): Implicit Type Conversion occurs automatically by the JavaScr

JavaScript typedArray.fill() Method

The typedArray.fill() is an inbuilt function in JavaScript which is used to fill a value to typedArray from a start index to end index. Syntax: typedarray.fill(value, start, end) Parameters: It takes three parameters that are specified below- value: It is the value to fill with typed array.start: It

How V8 compiles JavaScript code ?

V8 is a high-performance, open-source JavaScript and WebAssembly engine used by Google Chrome and Node.js. In this article, we will be going to see what happens behind the scene of V8 Architecture. There are basically three steps involved in processing the code: Parsing the codeCompiling the codeExe

What is Type Coercion in JavaScript?

JavaScript is a loosely typed or dynamic language, which means it automatically converts types when necessary, making it easier for developers to work with different data types in expressions, comparisons, and operations. However, this flexibility can sometimes lead to unexpected results if you're n