Re: about the next version

[Edgar Toernig <froese@...>]

Luiz Henrique de Figueiredo wrote:
> 
> >I'm not sure if the global statement is the right thing.
> 
> It's a new thing, and certainly not simple (or at least capable of being used
> in quite complicated ways), but we thing it does address a need. Or doesn't it?
> (The only snag right now is the need for "predeclarations".)

It does more.  As I see it, people want some kind of protection against mistyped
variable names.  One fundamental part of that is a way to easily know which
globals are exported by a module/file/library.  That is not addressed with the
current global statement (the 'snag' you mention: the core wants to export
globals without the need to import each one individually).

> The "global" declaration is for sophisticated uses, but I don't think it makes
> the language more difficult: it just let's you do complicated scope control.

And that is what I fear.  The simple 'global <name>' is easy and I have no
problem with that.  A method to let the compiler check for undefined names.

But the 'global ... in <table>' is something completely different.  It doesn't
address the mentioned 'need'.  It introduces a method for complicated dynamic
variable bindings and my fear is that you get even more complex rules (Which
identifier accesses which object?) than the rules in C++.  Reading sources
may become a nightmare.

In fact, I think that the 'global ... in <table>' has nothing to do with globals
any more.  It's a shorthand to access table fields (Pascal's with-statement).
A completely different topic.

Maybe it would be better to add only the simple 'global <name>'.  Then, for
Lua 6.0, think for some way to export globals to other files and add that.

My 2 cent, ET.