Pointers in Lua

[Xikue]

Hello. I was trying to go further with the flexible offensive aliases (http://mudlet.sourceforge.net/phpBB3/vi ... p?f=8&t=97) so that entering "kick rat" would also set your target to rat. (And following attacks would not need you to specify the target again.)
So I changed the tar function into this.

Code: Select all

function retarget(given)
   if given ~= nil then
      target = given
   end
      return target
end

But I have separate variables for targets in different activities (dtar, itar, otar) So I passed in the target variable as a parameter
ex. kick rat, pattern ^kick(\s(\w+))$

Code: Select all

send("kick " .. retarget(matches[3], otar))
--
function retarget(given, target)
   if given ~= nil then
      target = given
   end
   return target
end

Of course this failed because I didn't use a pointer. I found something called light user data which is supposed to be a void * pointer, but I don't understand how to use the functions they mentioned (such as lua_pushlightuserdata).

[Caled]

I don't understand the term 'pointer' but this doesn't seem all that complex a problem. The one thing missing is that (I am told) Lua doesn't seem to support recursive expansion of variables. The way around this being to stick your various target variables into a table.

Code: Select all

tars={
 otar="",
 itar="",
 dtar=""
}

function retarget(target, given)
	if given ~= nil then
		tars[target] = given
	end
	return tars[target]
end

Edit
I am not in a position to test that, but I -hope- that by switching the function parameters like that, this function will still work even when matches[3] in the alias is nil . At least, the function will work, but I am not sure if the alias itself will work.

If the alias refuses to call the function with a nil second parameter, then the problem is more complex. Well, even then the solution is simple enough, but it is not a solution I like - it involves putting more script in the alias itself, and in my opinion part of the point here is to make these aliases simpler to write as well as to use.

[Xikue]

Ah, I didn't switch the parameters and it still works with the table, so I guess it doesn't mind nil as the first parameter.
Thanks!