Re: 5.2: equality for closures

[Gé Weijers <ge@...>]

On Wed, 29 Jun 2011, Alexander Gladysh wrote:

> In our code we heavily use this function:
>
> local unique_object = function()
>    -- Note that table is not acceptable, since its contents are not constant.
>    return function() end
> end
>
> It returns globally unique constant object that then (usually) is used
> as a table key (usually to avoid name clashes).

You could use:

local function unique_object()
  local v = 0
  return function () v = v + 1; return v end
end

Each closure returned has a reference to a different 'v', and that is 
'discernable' if you call the function, so each call to unique_object 
returns a different closure.

Ge'