Re: modules, require, magic

[Sean Conner <sean@...>]

It was thus said that the Great Josh Simmons once stated:
> On Tue, Oct 18, 2011 at 6:20 PM, Sean Conner <sean@conman.org> wrote:
> >
> >  "But module() and require() could keep a private table with references to
> > each module and not dump them into the global space," you say.  Okay, but
> > you *still* need a global namespace, because DarkGod has *his* DNS module
> > (named dns) and I have *my* DNS module (which would also be named "dns"), so
> > which one is returned when you require("dns")?  (assuming that I have
> > modules I wrote using my DNS module, and some other modules I want to use
> > might be using DarkGod's DNS module)
> >
> 
> Require already does this, and you need to separate them at the
> filesystem level irregardless of what scope they're imported into.
> 
> local dns = require 'crazy.weird.dns'
> local dns2 = require 'somebody.elses.dns'
> 
> None of this has anything to do with global scope or module.

  My Lua paths have several locations where modules can lurk:

package.path:

	/home/spc/.luarocks/share/lua/5.1/?.lua
	./?.lua
	/usr/local/share/lua/5.1/?.lua
	/usr/local/lib/lua/5.1/?.lua
	/home/spc/work/ecid/tests/common/lua/?.lua

package.cpath:

	/home/spc/.luarocks/lib/lua/5.1/?.so
	./?.so
	/usr/local/lib/lua/5.1/?.so
	/home/spc/work/ecid/tests/common/lib/?.so

(that last path in each is for work related Lua stuff)

  And just doing a 

	require "dns"

will grab the first file matching dns.lua or dns.so, and woe to code that
expects CrazyWeird DNS module (living under /usr/local/lib/lua/5.1/dns.so)
and gets SomebyElse's DNS module (living under
/home/spc/.luarocks/lib/lua/5.1/dns.so).

  -spc (So yeah, the filesystem does this to a degree, but you can still
	get messed up ... )