Re: Introspection with Lua

[PA <petite.abeille@...>]

On May 16, 2006, at 04:49, Vineet Jain wrote:

> > I need to find out (dynamically) if a certain lua module has some 
> > functions and variables defined. I also need to set some module 
> > variables (dynamically).
> After some googling I came across _G, is this how you can check if a 
> function/variable exists in a lua module? Can you also use this to 
> dynamically assign variables to lua modules?

_G is the current environment.

And as mentioned by Romulo, a module is a table. Lookup the key you are 
after to check for membership:

local math = require( "math" )

if type( math.abs ) ~= "function" then
    math.abs = function() end
end

if math.PI == nil then
    math.PI = 3.14159265
end

Cheers

--
PA, Onnay Equitursay
http://alt.textdrive.com/