how to create a boolean function in javascript code example

Example 1: javascript can a var be a boolean

var YES = new Boolean(true);

Example 2: javascript function return boolean

function  func(){
  return true;
}

isBool = func();
console.log(typeof (isBool));   // output - string


let isBool = func();
console.log(typeof (isBool));   // output - boolean