A function object’s read-only name property indicates the function’s name as specified when it was created. If the function is anonymous it will be ''.

function myFunc1() {}
const myFunc2 = () => {};
const myFunc3 = function () {};
function receivesFunc(argFunc) {
  return argFunc.name;
}

console.log(myFunc1.name); // "myFunc1"
console.log(myFunc2.name); // "myFunc2"
console.log(myFunc3.name); // "myFunc3"
console.log(receivesFunc(myFunc1)) // "myFunc1"
console.log(receivesFunc(function myArgFunc() {})); // "myArgFunc"
console.log(receivesFunc(function () {})); // ""
console.log(receivesFunc(() => {})); // ""