@generic

---@generic T
---@generic T : ConstraintType
---@generic T, U, V

---@generic T
---@param value T
---@return T
function identity(value)
    return value
end

local x = identity("hello")  -- x is inferred as string
local y = identity(42)       -- y is inferred as number

---@generic K, V
---@param map table<K, V>
---@return K[]
function getKeys(map)
    local keys = {}
    for k in pairs(map) do keys[#keys+1] = k end
    return keys
end

---@generic T : Entity
---@param ent T
---@return T
function CloneEntity(ent)
    -- T must be Entity or a subtype (Player, NPC, etc.)
end

---@generic T
---@param items T[]
---@param predicate fun(item: T): boolean
---@return T[]
function filter(items, predicate)
    local result = {}
    for _, item in ipairs(items) do
        if predicate(item) then result[#result+1] = item end
    end
    return result
end

local players = filter(player.GetAll(), function(ply) return ply:IsAdmin() end)
-- players is typed as Player[]

---@class Entity
---@class sent_npc : Entity

---@generic T : Entity
---@param class `T`
---@return T
function ents.Create(class) end

local ent = ents.Create("sent_npc") -- inferred as sent_npc

---@generic T : Entity
---@param class `T`
---@return T[]
function ents.FindByClass(class) end

---@class aaa.`T`.bbb
---@class aaa.`T`
---@class `T`.bbb
---@class `T`

---@overload fun<T>(value: T): T
local function callGeneric(value)
    return value
end

local forced = callGeneric--[[@<number | string>]](1)