OOP objects in LUA

I am currently working on a operative system in LUA which is for computercraft, and I wanted to create a clickable GUI where I will want a function to create a button, but I god some issues using function cause I'd have to specify everything myself, so I wanted to create an Advanced OOP class.

For example in PHP I'd do

<?php
class button
{
  public clickEvent;
  public posX;
  public posY;
  private removeEvent;

  public function __contruct ( x, y, text, fg, bg ) {
    /* Code here */
  }

  /* ETC */

  public function clicked(...){...}
  public function removed(...){...}
}

$btn = [];
$btn[] = new button ( 1, 1, 'Hello world', colors.blue, colors.white );
?>

But how would I do this in LUA without having tons of functions that requires to do functonname (table, btn, parameters

Thanks in advance!

Im not sure (haven't done LUA for like a year) but i think you can do it like in JavaScript:

function button(x,y,text,fg,bg)
  obj = {
	clickEvent = nil,
	posX = nil,
	posY = nil,
	removeEvent = nil,
	-- ETC --
	clicked = function (...) end,
	removed = function (...) end
  }
  -- Construct here --
  obj.posX = x
  obj.posY = y

  -- return --
  return obj
end

COOLGAMETUBE's example is more or less how the window API creates "window" objects. It's also possible to do much the same thing without defining the same functions over and over by creating funcs intended to be called using colon notation; and if you don't even want to bother sticking those pointers into your new object tables manually, metatables can handle that for you. The latter methods are how the vector API operates.

The best way of implementing classes and objects is probably through Lua's metatable feature. This especially comes in handy if you want your classes to inherit from other classes.

*shameless self promotion*

I wrote a library that should have everything you showed in your example, defining classes, making members public/private etc.
You might want to check it out if you are interested in how it works.

Kouksi44, on 03 February 2017 - 03:08 PM said:

The best way of implementing classes and objects is probably through Lua's metatable feature. This especially comes in handy if you want your classes to inherit from other classes.

*shameless self promotion*

I wrote a library that should have everything you showed in your example, defining classes, making members public/private etc.
You might want to check it out if you are interested in how it works.

Interesting, where can I have a look?

That's the forum post: http://www.computercraft.info/forums2/index.php?/topic/26305-classic-pretty-oop-in-cc/page__pid__264250__st__20#entry264250

I think Kouksi44 meant this post…

TechnicalCoding, on 02 February 2017 - 10:51 PM said:

But how would I do this in LUA without having tons of functions that requires to do functonname (table, btn, parameters

You could use Titanium, which provides a custom class system allowing you to create custom nodes (nodes are buttons, and text boxes, etc…) if the default ones (listed in the forum post) don't cut it for you (source).