Re: Local as table

[steve donovan <steve.j.donovan@...>]

On Thu, Feb 21, 2013 at 8:50 PM, James Graves
<james.c.graves.jr@gmail.com> wrote:
> import { _ENV,
>     baz = "foo.bar",
>     math_iz_awezome = "math",
>     "os",
> }
>
> Hmmmm.... maybe I should write that up.

That is very Go-ish indeed. The _ENV could be implicit (import could
look it up as upvalue of calling function, or fall back to getfenv).

A cool feature is that 'require' is implicit here.

But now, how about the 'leaky module' problem, which is why
module(...,package.seeall) got such a bad rap?  Your new module will
be displaying its underwear, e.g. we could access os, which might very
well be a no-no in another context.

One solution would be to use a shadow table - you put everything you
want into _ENV, but keep an _actual_ module table; _ENV will have a
__newindex which will write any new functions into the module table.
One just has to remember to return that module, not _ENV itself.

(Very much on my mind because I'm revisiting Penlight's strict mode
and generalizing it for modules; Andrew has suggested a most
entertaining import mechanism but I'm worried about the underwear
problem)

steve d.