Generic for Operator

[sevenninesixthree]

For example,

local unit
---@class Factor<T,U>:{f:fun(x:T):U}
---@operator

---@generic T
---@class Factor<T>
local Factor={
  ---@generic T,U,V
  ---@param f Factor<U,V>
  ---@param g fun(x:T):U
  ---@return Factor<T,V>
  __mul=function (f,g)
    return unit.factor(function (x)
      return f.f(g(x))
    end)
  end
}
Factor.__index=Factor
---@generic T,U
---@param f fun(x:T):U
---@return Factor<T,U>
function unit.factor(f)
  return setmetatable({f=f},Factor)
end
---@param x integer
---@return integer
local function f(x)
  return x+1
end
---@param x integer
---@return integer
local function g(x)
  return x*2
end

local h1=unit.factor(f):__mul(g)
local h2=unit.factor(f)*g

What should be added behind operator to make sure that the server can get h2's type correctly like h1?