Classic
A tiny class module for Lua. Attempts to stay simple and provide decent performance by avoiding unnecessary over-abstraction.
Usage
The module should be dropped in to an existing project and required by it:
Object = require "classic"The module returns the object base class which can be extended to create any additional classes.
Creating a new class
Point = Object:extend()
function Point:new(x, y)
self.x = x or 0
self.y = y or 0
endCreating a new object
local p = Point(10, 20)Extending an existing class
Rect = Point:extend()
function Rect:new(x, y, width, height)
Rect.super.new(self, x, y)
self.width = width or 0
self.height = height or 0
endChecking an object's type
local p = Point(10, 20)
print(p:is(Object)) -- true
print(p:is(Point)) -- true
print(p:is(Rect)) -- false Using mixins
PairPrinter = Object:extend()
function PairPrinter:printPairs()
for k, v in pairs(self) do
print(k, v)
end
end
Point = Object:extend()
Point:implement(PairPrinter)
function Point:new(x, y)
self.x = x or 0
self.y = y or 0
end
local p = Point()
p:printPairs()Using static variables
Point = Object:extend()
Point.scale = 2
function Point:new(x, y)
self.x = x or 0
self.y = y or 0
end
function Point:getScaled()
return self.x * Point.scale, self.y * Point.scale
endCreating a metamethod
function Point:__tostring()
return self.x .. ", " .. self.y
endLicense
This module is free software; you can redistribute it and/or modify it under the terms of the MIT license. See LICENSE for details.