Table of contents
PermalinkSyntax Error
A Syntax error is caused due to incorrect usage or a typo in your code.
Some examples include -
- Missing or invalid opening/closing Brackets
[...]
, Parentheses(...)
or Curly braces{...}
function printNum(num) {
console.log(num);
- Missing or invalid semicolons
"
or colons'
console.log("Abhishek');
- Typo in variable name or function.
comst myName = "Abhishek";
PermalinkReference Error
A Reference error occurs when a variable
or a function
is used that does not exist or is out of scope. For example -
- Accessing a variable before Declaring.
console.log(a);
- Accessing a variable before Initializing.
console.log(age);
let age = 23;
- Declaring a variable without a variable name in
strict mode
"use strict"
age = 23;
console.log(age);
- Out of Scope variable
function getUserInfo() {
const userName = "Abhishek";
}
console.log(userName);
PermalinkType Error
Type error occurs when some value doesn’t turn out to be of a particular expected type. For example -
- Using
String
Upper/Lower Case operation onInteger
const age = 20;
console.log(age.toUpperCase());
- Calling variables as functions
let userInfo;
userInfo();
- Updating a value that cannot be changed
const num1 = 10;
num1 = 20;
There are many ways an error can happen but these are some common types of errors and how they occur. Hope you learned something and thanks for reading.