Re: Forward declarations in modules

[Nick Gammon <nick@...>]

On 08/09/2006, at 9:14 AM, Jerome Vuarand wrote:

> Here you can see that you have two and only two variable creations.  
> That's why you have two different printed values.

Yes I see what is happening, but the surprising thing is that local  
variables behave so much differently to other types of variables.

eg.

a = 5  -- add to _G.a
a = 6  -- replace _G.a


however

local a = 5  -- make a local variable named a
local a = 6  -- make a completely different variable named a

The Lua book notes that "access to local variables is faster than to  
global ones".

I would have to guess from this example that a local variable is,  
effectively, a fixed piece of memory that involves no table lookups  
(nor metatables), however access to global variables involves at  
least one table lookup.

- Nick