readme.md


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# Object.lua
## Description
**Object.lua** is a really small lua module used for class creation that supports single-parent inheritance (Java-like) and metamethods. Initially it was created with three different approaches for fun but it eventually matured enough to be used. It was tested and works just fine on Lua 5.1 and up.
## Example
```lua
local Object = require "Object"

local Point = Object:extends() -- creating new class by extending basic class
function Point:new (x, y) -- defining function called by constructor for newly created class
	self.x = x -- instance created by constructor is `self`
	self.y = y
end -- no returns needed

Point.NUMBER = 10 -- setting some global values for class

function Point:__tostring () -- metamethod used with `tostring()`
	return "Point<" .. self.x .. ", " .. self.y .. ">"
end

local a = Point(3, 2) -- create new instance by calling class
print(tostring(a))

assert(a:is(Point))  -- you can also check if object is instance of class
assert(a:is(Object)) -- use `is()` method for it

local Foo = Point:extends() -- you can extend whatever class you want
function Foo:new (str, x, y)
	Foo.__super.new(self, x, y) -- call super constructor first
	self.str = str -- do whatever else is left to be done
end

function Foo:__tostring () -- metamethods are not inherited
	return "Foo(" .. self.str .. ")<" .. self.x .. ", " .. self.y .. ">"
end

local b = Foo("lorem", 7, -1)
print(tostring(b))
```