Classes and Objects

A class is an user defined data structure. It's made out of members and member functions. Those members and member functions can be then accessed by creating an object from that class. Think of a class as a blueprint for an object.

Creating a Class

Here's an example of a person class:

local class = ClassPP.class

local person = class "Person" {
    Public = {
        Name = "",
        Age = 0
    }
}

To create a new class, you use the class() function, with the above syntax, the first argument will be a string that defines the name of the class, and the second argument is the class data, a table that contains all the access specifiers and the member data.

In the above example, we created a new class with the name Person, and we created two members, named: Name and Age.
Then, we assigned default values to them. These values will be transferred to the object when it gets created.

Creating an Object

Now that you have learned how to create classes, it's time to learn how to create objects. In Class++, to create an object you use the class.new() function. This function returns an object created from this class, and will contain all of the members that you defined.

local class = ClassPP.class

local person = class "Person" {
    Public = {
        Name = "",
        Age = 0
    }
}

local newPerson = person.new()
print(newPerson.Age) -- Prints "0"!

Objects will have the members and their default values that you've set in the class data table, so if you want to update them, you can simply index the object with the member and set it to something else!

local class = ClassPP.class

local person = class "Person" {
    Public = {
        Name = "",
        Age = 0
    }
}

local newPerson = person.new()
newPerson.Age = 21

print(newPerson.Age) -- Prints "21"!

Warning

Unlike the classic class method on Roblox that developers use, in Class++, to define a member you must do it through the class() function, trying to define a new member through the object will result in an error.

local class = ClassPP.class

local person = class "Person" {
    Public = {
        Name = "",
        Age = 0
    }
}

local newPerson = person.new()
newPerson.Personality = "Cheerful" -- This will error! This class has no member named "Personality".