Re: [Module-build-general] use only The::Finest => 1.23;

[Brian I. <in...@tt...>]

On 19/02/03 11:00 -0600, Ken Williams wrote:
> 
> On Wednesday, February 19, 2003, at 12:46  AM, Brian Ingerson wrote:
> > I've just released a module called 'only.pm' that allows people to
> > install multiple versions of various modules. It also lets them 'use'
> > specific versions.
> 
> I saw that flash by on the CPAN-recent list.  Looks good to me.  Glad 
> it cooperates with M::B, and a patch for more explicit support would be 
> welcome.  I'm not in an environment where I'd use it much, but I know 
> those environments do exist when tight controls are necessary.
> 
> The only reservation I have is that it introduces a new syntax for 
> version number specs, and M::B already has something similar but 
> different.  It's not really essential to use the same syntax, but maybe 
> some cooperation would be good.  Hopefully someone will have some good 
> ideas about it in response to my "mini-language" post from yesterday.
> 
> >           # Only use MyModule if version is between 0.30 and 0.50
> >           # but not 0.36; or if version is >= to 0.55.
> >           use only MyModule => '0.30-0.50 !0.36 0.55-', qw(:all);
> 
> I'm not sure I understand when the parts are and-ed together and when 
> they're or-ed together.  The above seems to mean
> 
>           (0.30-0.50 and !0.36) or 0.55-
> 
> or maybe actually
> 
>           (0.30-0.50 or 0.55-) and !0.36

Aren't those the same? For what version would they have a different
effect?

Basically every condition is ORed together, but complements are ANDed.
Complements also short circuit. From the doc:

    If a module version matches a complement, that version is
    immediately rejected without further inspection.

I guess I need a more formal phrasing. Ideas?

I'll take a look at M::B's syntax.

Cheers, Brian