Re: package proposal

[David Jones <drj@...>]

On Sep 17, 2004, at 17:49, Roberto Ierusalimschy wrote:

> This is a proposal for a more standard package usage in Lua.  It
> includes some changes in the `require' function, some changes in the
> `luaL_openlib' function, and a new function `module'. We already got
> previous comments about this proposal from Diego Nehab (LuaSocket),
> Andre Carregal (Kepler) and Tomas Gorham (Kepler).

Finally got round to reading this post.

I like it.

I have a couple of points of uneasiness (some mentioned by other people 
in the thread):

1) Distinction between packages and modules seems unnecessary.  Allow 
module A to drag in other modules  if necessary.

2) Can we have "./?;" in the default package.path like require 
currently has?

3) It prefers binary modules over lua modules.  I'm exactly sure what 
to think about this.  Obviously it makes tweaking or subverting a 
binary lua module harder, but I don't use binary lua modules, so I 
don't have any experience to draw on.

4) A given lua file that implements a module may exist in more than 
place in the filesystem.  A trivial example is a case-insensitive 
filesystem on Mac OS X.  << require 
"Trace";require"trace";require"TRACE" >> will pull in the same file 3 
times.  It seems undesirable that I should be able to go << 
require'trace' >> and the module gets plonked in the global trace, but 
if I go << require 'Trace' >> is still works, but the same module gets 
plonked in the global Trace.  An obvious solution is to downcase all 
module names before using them (and perhaps make the downcase function 
user over-ridable?).  I personally would prefer module names of the 
form 'Trace', 'String', etc, but that's not the current Lua style, and 
downcasing seems better globally.


It would be nice to have some standard info about modules (such as 
author, help, license, and so on) but I don't think that now is the 
right time to discuss that.

David Jones