Re: [Suggestion] Passing upvalues to load()

["Claire Lewis" <claire_lewis@...>]

> > How does order factor in, if the code refers to them by name? I think
> > I'm overlooking something.
> In Rio Lua, the order is as they appear. So if a global access appears 
> before any other upvalue access on a function, _ENV is the first upvalue.
>
> local u2, u3, u4, u5
> function()
>    print(u2, u3, u4, u5) -- _ENV is the first upvalue, because "print" is 
> actually "_ENV.print" (or "_ENV['print']")
> end

Unless I'm missing something, I don't think this is reliable, that's an 
implementation detail, and could change any future version, even a patch 
release of 5.3.

The Lua 5.3 manual states: "Upvalues have no particular order, as they are 
active through the whole function. They are numbered in an arbitrary order."

I'd probably recommend finding a different way to achieve this for a public 
module.

- Claire