DouKaku?

function locals()
   local i = 1
   local t = {}
   while true do
     local k, v = debug.getlocal(2, i)
     if k == nil then break end
     t[k] = v
     i =  i + 1
   end
   return t
end

function foo()
  local x = 1
  local y = "hello"
  return locals(), nil
end

for k, v in pairs(foo()) do print(k, v) end 
--> y       hello
--> x       1