setfenv for the whole thread

["Renato Maia" <renatofigueiro@...>]

Hi everybody,

I'm having some problems to understand the semantics of 'setfenv' function
(I've read some previous messages posted about similar subjects but I couldn't
figure it out). I'd like to set the global environment of a whole coroutine
thread to some table I own. According to Lua manual this is possible by
calling 'setfenv(0, my_environ)' (unless I'm horribly mistaken), but in
the following example I couldn't get the desired behavior, since neither
the coroutine thread main function nor other called functions seems to see
the environment I set previously. However some default Lua functions like
the 'print' function seems to be aware of the defined environment.

--------------------------------------------------------------------
-- Example

var = "global"

local old = tostring
local context = {
	var = "local",
	tostring = function(val) return "#" .. old(val) .. "#" end,
	print = print,
}

local function run(func)
	local thread = coroutine.create(
		function()
			setfenv(0, context)
			print(var)          -- runs with 'context' as its environment
			return var, func()  -- run with original global environment
		end
	)
	return coroutine.resume(thread)
end

print(run(function() return var end))
--------------------------------------------------------------------

By the example above I expected to have the following output:

> #local#
> true    local  local

but I got...

> #global#
> true    global  global

Does anybody could please tell me what to do to get what I want?

Thanks everybody,

Renato Maia.