RE: [Tile-dev] Re: tile 0.5 binary for MacOSX X11

[Jeff H. <je...@Ac...>]

> > If package Tk is not present at the time of [package require Tile 
> > 0.5], then the Tile package will not be found.  The index script(s) 
> > above require the application to do:
> >
> >     package require Tk 8.5
> >     package require Tile 0.5
> >
> > in order.  Since I cannot imagine any application that will use Tile 
> > commands that would not also use Tk commands, I don't think this 
> > limitation imposes any burden.
> 
> OK, that answers my question. You are assuming that Tk is present.
> 
> No problems - I agree that it isn't an undue burden. But it is a change 
> from the current situation.
> 
> What do others think?

I don't like it because you are forcing an error situation
every time that pkgIndex.tcl is hit.  catch'es with errors
are actually expensive.  I think it should avoid those
situations, instead being a bit more refined to not error
as much (same general code-path, just slightly different).
I'm not sure exactly what was intended from the original
design, but something more like:

if {[info tclversion] != 8.4} { return }
if {[package provide Tk] eq ""} { return }
 ....

Note that you can't use 'eq' in an expr before checking 8.4+
compatability.

Jeff