lexically scoped string methods

gistfile1.lua

--[[
11:22:54	daurnimator	I've always thought local string metatables etc would be cool
11:23:02	daurnimator	I'd want them lexically scoped
11:24:54	daurnimator	you could make it so that string's __index used debug.getlocal to find the _ENV
11:25:22	daurnimator	that way mystring.foo would always be equal to _ENV.string.foo
]]

string = {
	sub = function()
		return "something else"
	end;
}

print("PRE", ("foo"):sub(2))

local string_mt = debug.getmetatable("")
local strsub = string_mt.__index.sub
function string_mt:__index(k)
	local func = debug.getinfo(2, "f").func
	local name, env = debug.getupvalue(func, 1)
	if name == "_ENV" or (name ~= nil and strsub(name, 1, 1) == "(") then
		local env_string = env.string
		if env_string ~= nil then
			return env_string[k]
		end
	end
end

print("POST", ("foo"):sub(2))