require "oop.class"
require "oop.mixin"
require "oop.property"
require "oop.enum"

Fmt = require "oop.fstrings"
Handler = require "oop.handler"
Option = require "oop.option"
Try = require "oop.try"

-- local function upvalue_find(func, key)
--     assert("string" == type(key))
--     local index = 1
--     local iKey
--     local iValue
--     repeat
--         iKey, iValue = debug.getupvalue(func, index)
--         if iKey == key then
--             return iValue, index
--         end
--         index = index + 1
--     until nil == iKey
-- end

-- local function upvalue_replace(func, key, value)
--     local _, index = upvalue_find(func, key)
--     if index then
--         debug.setupvalue(func, index, value)
--         return true
--     else
--         return false
--     end
-- end