-
Notifications
You must be signed in to change notification settings - Fork 5
/
class.lua
65 lines (62 loc) · 1.52 KB
/
class.lua
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
--
--------------------------------------------------------------------------------
-- File: class.lua
--
-- Usage: ./class.lua
--
-- Description:
--
-- Options: ---
-- Requirements: ---
-- Bugs: ---
-- Notes: ---
-- Author: YOUR NAME (), <>
-- Organization:
-- Version: 1.0
-- Created: 15.04.2021
-- Revision: ---
--------------------------------------------------------------------------------
--
local function class(base, init, defaults)
local c = defaults or {} -- a new class instance
if not init and type(base) == 'function' then
init = base
base = nil
elseif type(base) == 'table' then
-- our new class is a shallow copy of the base class!
for i,v in pairs(base) do
c[i] = v
end
c._base = base
end
-- the class will be the metatable for all its objects,
-- and they will look up their methods in it.
c.__index = c
-- expose a constructor which can be called by <classname>(<args>)
local mt = {}
mt.__call = function(class_tbl, ...)
local obj = {}
setmetatable(obj,c)
if init then
init(obj,...)
else
-- make sure that any stuff from the base class is initialized!
if base and base.init then
base.init(obj, ...)
end
end
return obj
end
c.init = init
c.is_a = function(self, klass)
local m = getmetatable(self)
while m do
if m == klass then return true end
m = m._base
end
return false
end
setmetatable(c, mt)
return c
end
return class