Module:Nullish

可在Module:Nullish/doc创建此模块的帮助文档

local null, nullish
nullish = function(v) return v == null or v == nil end
null = setmetatable({}, {
    __newindex = function() return end,
    __concat = function(a, b)
        return b == "" and tostring(a) or (a .. "") .. (b .. "")
    end,
    __tostring = function() return "null" end,
    __call = function() return nil end,
    __div = function(a, b)
        if nullish(a) then return b end
        return a
    end
})
return null, nullish