classes

Classes, or structs, are a way to group a collection of values together, similiar to a mapping. A class holds a pre-defined number of member values which are accessed by their given name.

To use a class across multiple code files, it is ideal to have a shared inheritable for the class definition. Do not use include statements.

Define what the class will look like:

class Person {
    string name;
    int level;
}

Create an empty instance of the Person class:

    class Person npc = new(class Person);

Create an instance of the Person class with passed values:

    class Person npc = new(class Person, name: "Name", level: 15);

Accessing member values using dot operator:

    npc.name = "Name";
    npc.level = 15;

Accessing member values using arrow operator:

    npc->name = "Name";
    npc->level = 15;

Casting a class:

function (mixed p, string name) {
    ((class Person)p)->name = name;
}

classp(value) is true for class instances. A class is a fixed layout (named members), not a mapping: you cannot add keys at runtime, and two instances of the same class do not share identity just because their fields match.

To share a class definition across files, put the class declaration in an inheritable and inherit it. Do not #include the declaration — each include creates a distinct class type even if the members look the same.

new(class Person, name: "Ada", level: 15) is the usual constructor. new("/obj/sword") is unrelated: that form clones an object. See objects.