#29 Try it out


TypeError: olderAge is not a function

What did I do wrong ? :weary:

// Our person constructor
function Person (name, age) {
    this.name = name;
    this.age = age;
// We can make a function which takes persons as arguments
// This one computes the difference in ages between two people
var ageDifference = function(person1, person2) {
    return person1.age - person2.age;
// Make a new function, olderAge, to return the age of
// the older of two people
// Let's bring back alice and billy to test our new function
var alice = new Person("Alice", 30);
var billy = new Person("Billy", 25);

console.log("The older person is " + olderAge(alice, billy));
var olderAge = function(person1, person2) {
    if ( person1.age > person2.age ) {
        return person1.age;
} else { 
    return person2.age; 


It is not defined until the next line, so no, it is not a function, yet. Move this line to below the function body (the very end) and it will then be a valid reference.


Thanks :grinning:
You helped me a lot :grin: