Re: linked variable

[Rici Lake <lua@...>]

1) Actually, lua_getglobal does not do . resolution.

2) However, there is an undocumented interface in lauxlib, 
luaL_findtable(). This doesn't actually do what you want either, but it 
shows how you might write such a function in c.

In Lua, it's pretty easy:

function getdotted(field, start)
  start = start or _G
  for k in field:gmatch"[^.]+" do
    start = start[k]
    if start == nil then break end
  end
  return start
end

3) Please figure out how to turn off HTML mail for list submissions

4) Sorry for top-posting


On 1-Dec-06, at 12:27 PM, wang xu wrote:

> Jim,
>
> Thanks! It works.
>
> I also tried to change the value:
> > =loadstring("return "..path_to_n2)()
>  hello
>  > =loadstring(path_to_n2.."='world'")()
>  > =n1.n2
>  world
>  >
>
> However, I'm not feeling comfortable with it..
>
> To make it looks a little bit nicer..Maybe I need to wrap 
> lua_getglobal/lua_setglobal in C, and then I can use:
>
> getglobal(path_to_n2)
> setglobal(path_to_n2, "a new value for n1.n2")
>
> Or, is it meaningful for Lua to add a dynamic resolving operator?
>
> 2006/12/2, Jim Whitehead II <jnwhiteh@gmail.com>:
> >  You can use loadstring, i.e.
> >
> >  Lua 5.1.1  Copyright (C) 1994-2006 Lua.org, PUC-Rio
> >  > t = {a = true}
> >  > =loadstring("return t.a")()
> >  true
> >  >
> >
> >  In your case something like this should work:
> >
> >  loadstring("return " .. path_to_n2)()
> >
> >
> > On 12/1/06, wang xu <xu4wang@gmail.com> wrote:
> > > If I have a string containing the path to a varialble, for example:
> > >
> > > > n1={n2="hello"}
> > > > =n1.n2
> > > hello
> > > > path_to_n2="n1.n2"
> > > > print(path_to_n2)
> > > n1.n2
> > > >
> > >
> > > Given variable path_to_n2, how can I get the value of n1.n2 ?
> >