In Lua, classes are tables, tables of tables etc ..
The Lua classes tutorial is not yet translated on Inspired-Lua, you can try a google translate, but some people says they didn't understand it =/
http://www.inspired-lua.org/2011/05/5-object-classes/I'm going to sum up
If toto is a class and x,y numbers of this class, f1, f2 functions of this same class, and tab a table also in this class.
Then :
toto = {
x=1,
y=2,
f1=function() return true end,
f2=function() return false end,
tab={
.....
}
}
Then you can access to toto.x, toto.y, etc ...
But this is a fixed way to do "classes".
The TI-Nspire Lua framework contains a function that is not part of Lua 5.1 : class()
This function avoids typing multiple lines that many of us won't understand (even if it is quite simple)
With the same example :
toto = class()
function toto:init()
self.x, self.y = 1, 2
self.f1 = function() return true end
self.f2 = function() return false end
self.tab = {...}
end
init() function is required by class(). When you want to create a new toto object, you will do like this : a = toto()
You can give to init() arguments to create a specified object like this :
function toto:init(x0, y0)
self.x, self.y = x0, y0
self.f1 = function() return true end
self.f2 = function() return false end
self.tab = {...}
end
Then, you will be able to do : a = toto(1,2) and access to a.x and a:f1
Remember another thing in Lua : the difference between . and : between the object and its element :
a.x access to x element in object a
a.f1() access to f1 function in object a
a:f1() access to f1 function in object a and gives to f1 function a as first argument, that way you can use 'self' in its définition.
a.f1(a) == a:f1()
function a.f1(parent) return parent.x end == function a:f1() return self.x end
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