Mixin

A deep copying mixin utility for Luau with full type support and zero dependencies.

Why?

Merge tables without writing for loops manually, with safe deep cloning and full autocomplete support out of the box.

Quick Start

local Mixin = require(ReplicatedStorage.Packages.Mixin)

local A = { HP = 100, Speed = 10 }
local B = { HP = 50, Damage = 5 }

local C = Mixin(A, B)

C.HP -= 50

print(A.HP) -- 100, untouched because C is a deep copy, not a reference to A
print(C.HP) -- 0, because B overwrote A's HP

Extra

Example of how Mixin can be used in OOP to replace inheritance with composition

local Mixin = require(ReplicatedStorage.Packages.Mixin)

local Animal = require("./Animal")

export type Type = Animal.Type & {
    Bark: (self: Type) -> (),
    IsAngry: boolean
}

local Dog = {} :: Type
Dog.IsAngry = false --Default properties here, mixin will copy them
Dog.IsHungry = true --Derived from Animal, overriding 

local Constructor = {}

function Constructor.new(): Type
    return Mixin(
        Animal.new(),
        Dog
    ) --No metatables used, copying everything from Animal and Dog
end

function Dog:Bark()
    print("Woof!")
end

return table.freeze(Constructor)

Installation

Add to your wally.toml:

[dependencies]
Mixin = "pocketpremium/mixin@1.0.0"