String.prototype.trimStart()

Baseline

20201

trimStart() String trimLeft()

const greeting = "   Hello world!   ";

console.log(greeting);
// : "   Hello world!   ";

console.log(greeting.trimStart());
// : "Hello world!   ";

trimStart()

trimLeft()

str

str str

trim() trimLeft padStart() trimStart trimLeft trimStart

String.prototype.trimLeft.name === "trimStart";

str

let str = "   foo  ";

console.log(str.length); // 8

str = str.trimStart();
console.log(str.length); // 5
console.log(str); // 'foo  '


ECMAScript 2027 LanguageSpecification # sec-string.prototype.trimstart

MDN

MDN 2025822

GitHub