local upvalue1 = "upvalue1"
local upvalue2 = "upvalue2"
local upvalue3 = "upvalue3"

do
    local upvalue4 = "upvalue4"
end

-- assume upvalues is a table containing all the upvalues in this scope
for key, val in pairs(upvalues) do
    print(key, val)
end

-- 3, upvalue3
-- 2, upvalue2
-- 1, upvalue1

-- upvalue4 does not exist in this scope