Javascript:TrimLeft & TrimRight

function trimLeft(str) {

  if (typeof str !== 'string') {

    throw new TypeError('Expected a string');

  }

  return str.replace(/^\s+/, '');

}

function trimRight(str) {

  if (typeof str !== 'string') {

    throw new TypeError('Expected a string');

  }

return str.replace(/\s+$/, '');

}

let input = '   Hello, World!   ';

let trimmedLeft = trimLeft(input);

console.log("'" + trimmedLeft + "'"); // Output: 'Hello, World!   '

let trimmedRight = trimRight(input);

console.log("'" + trimmedRight + "'"); // Output: '   Hello, World!'