Arderas Link Library 2

local links = {}
local slinks = {}
local cslinks = setmetatable({}, {__index = function(t, k) return slinks[k]() end})
local adresstolink = {}
local adresstoslink = {}

local __eq_l = function(a, b)
    return adresstolink[a] == adresstolink[b]
end

local __eq_sl = function(a, b)
    return adresstoslink[a] == adresstoslink[b]
end

function link(val, id)
    local wrong_type = "Link Value must be a byval type. (number, string, boolean, nil)"
    if not id then
        id = math.random()
        while links[id] do
            id = math.random()
        end
    end

    if type(val) == "number" or type(f) == "string" or type(f) == "boolean" then
        links[id] = val
    elseif type(val) ~= "nil" then
        error(wrong_type, 2)
    end

    local l = setmetatable({}, {
        __newindex = function(t, k, v)
            if k == "s" and (type(v) == "number" or type(v) == "string" or type(v) == "boolean" or v == nil) then
                -- only byval types allowed
                links[id] = v
            else
                error(wrong_type, 2)
            end
        end,
        __index = function(t, k)
            if k == "g" then
                return links[id]
            end
        end,
        __call = function()
            return link(nil, id)
        end,
        __metatable = "link",
        __tostring = function()
            return tostring(links[id])
        end,
        __unm = function()
            return -links[id]
        end,
        __add = function(a, b)
            return links[id] + b
        end,
        __sub = function(a, b)
            return links[id] - b
        end,
        __mul = function(a, b)
            return links[id] * b
        end,
        __div = function(a, b)
            return links[id] / b
        end,
        __mod = function(a, b)
            return links[id] % b
        end,
        __pow = function(a, b)
            return links[id] ^ b
        end,
        __concat = function(a, b)
            return tostring(links[id]) .. tostring(b)
        end,
        __eq = __eq_l
    })
    adresstolink[l] = id

    return l
end

fslink = 0

function slink(f, id)
    local wrong_type = "Stronglink value must be a byval type (number, string, boolean, nil) or a function."
    if not id then
        id = math.random()
        while slinks[id] do
            id = math.random()
        end
    end

    if type(f) == "function" then
        slinks[id] = f
    elseif type(f) == "number" or type(f) == "string" or type(f) == "boolean" then
        slinks[id] = function() return f end
    elseif type(f) ~= "nil" then
        error(wrong_type, 2)
    end

    local l = setmetatable({}, {
        __newindex = function(t, k, v)
            if k == "s" and (type(v) == "number" or type(v) == "string" or type(f) == "boolean" or v == nil) then
                -- only byval types allowed
                slinks[id] = function() return v end
            else
                error(wrong_type, 2)
            end
        end,
        __index = function(t, k)
            if k == "g" then
                return cslinks[id]
            end
        end,
        __call = function()
            return slink(nil, id)
        end,
        __metatable = "stronglink",
        __tostring = function()
            return tostring(cslinks[id])
        end,
        __unm = function()
            return slink(function() return -cslinks[id] end)
        end,
        __add = function(a, b)
            return slink(function() return cslinks[id] + b end)
        end,
        __sub = function(a, b)
            return slink(function() return cslinks[id] - b end)
        end,
        __mul = function(a, b)
            return slink(function() return cslinks[id] * b end)
        end,
        __div = function(a, b)
            return slink(function() return cslinks[id] / b end)
        end,
        __mod = function(a, b)
            return slink(function() return cslinks[id] % b end)
        end,
        __pow = function(a, b)
            return slink(function() return cslinks[id] ^ b end)
        end,
        __concat = function(a, b)
            return slink(function() return tostring(cslinks[id]) .. tostring(b) end)
        end,
        __eq = __eq_sl
    })

    adresstoslink[l] = id

    return l
end