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core/class.lua — class factory

The in-house object-oriented class factory that builds every RitnLib class (and its consumer mods'). Single inheritance, callable constructor, type test — in Lua 5.1, dependency-free. The why of this choice is in ADR-0001.
Source core/class.lua
Stage all (loaded at bootstrap)
Access ritnlib.classFactory (global) or require(ritnlib.defines.class.core)
object_name (type) "RitnClassFactory"

Functions

newclass(super, init) → table

Creates a new class, with optional inheritance.

  • No parent: newclass(initFn) — the first argument is the init function.
  • With parent: newclass(ParentClass, initFn) — shallow-copies the parent's fields into the child + c._super = ParentClass.

The returned class is callable: MyClass(args) creates an instance, sets the class as its metatable (__index), then runs init(obj, ...). Each instance gains :is_a(klass), which walks the _super chain.

Parameters - super :: table|fun(self, ...) — parent class (inheritance) or init function (no parent). - init :: fun(self, ...)? — init function (required only when the 1st arg is a parent class).

local A = ritnlib.classFactory.newclass(function(self, arg) self.value = arg end)
local B = ritnlib.classFactory.newclass(A, function(self, arg)
    A.init(self, arg)      -- explicit parent-constructor call
    self.extra = 42
end)
local obj = B(10)
obj:is_a(A)                -- true

new(super, init) → table

Warning — Deprecated / unused. Alternative variant of newclass kept during early development, referenced nowhere. Scheduled for removal — don't write new code against it.

Instance method

:is_a(klass) → boolean

Present on every instance: true if klass is the instance's class or one of its ancestors (walks _super).

Remarks

  • ⚠ Shallow-copy — the parent's fields are shallow-copied into the child: a table defined at class level stays shared by reference. Harmless in practice (fields are (re)assigned in init), but worth knowing.
  • Explicit parent constructor — you must call Parent.init(self, …) by hand in the subclass (no automatic super()).
  • Single inheritance only — no mixins / multiple inheritance.

See also