Re: Object system

[Raffaele Salmaso <raffaele@...>]

Raffaele Salmaso wrote:
> Please test it, abuse it and find obscure bugs or improve it.
Ok, a little improved version. I forgot to check the existance of 
klass.init function.

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--
-- Copyright (C) 2004, Salmaso Raffaele <raffaele@salmaso.org>
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-- operator overloading
-- __add +
-- __mul *
-- __sub -
-- __div /
-- __le <=
-- __lt <
-- __eq ==
-- __tostring
-- __call ()
-- __index []
-- __newindex
-- __pow ^
-- __unm
-- __concat ..

function class(super)
	-- create a new class description
	local klass = {}
	-- set the superclass (for object inheritance)
	setmetatable(klass, {
		__index = super,
		__call = function(self, ...)
			tmp = {}
			setmetatable(tmp, klass)
			if self.init then
				self.init(tmp, unpack(arg))
			end
			return tmp
		end
	})
	klass.__index = function(table, key)
		local r = klass[key]
		if table ~= klass and type(r) == 'function' then
			return function(...) r(table, unpack(arg)) end
		else
			return r
		end
	end
	return klass
end

-- ######################
-- test the object system
-- ######################

object = class()
function object.method(self)
	print(self, 'object.method')
end

o=object()
m1 = o.method
m2 = object.method
m1()
m2()
m2(o)