Variables should not be initialized to
undefined JS-0126
Anti-pattern
Minor
2 years ago
—
2 years old
It's not necessary to initialize 'error' to undefined.
1let fail = false;
2let error = undefined; 3
4let lastUrl = "";
5let isWhitelist = false;
Description
In JavaScript, a variable that is declared and not initialized to any value automatically gets the value of undefined. For example:
var foo;
console.log(foo === undefined); // true
It's therefore unnecessary to initialize a variable to undefined, such as:
var foo = undefined;
It's considered a best practice to avoid initializing variables to undefined.
Bad Practice
var foo = undefined;
let bar = undefined;
Recommended
var foo;
let bar;
const baz = undefined;