ports with bootstrapping dependencies

[Ryan Schmidt]

On Jun 25, 2007, at 09:46, Taylor R Campbell wrote:

> Actually, it occurs to me that it's not really necessary to declare a
> dependency -- that it would suffice for the variant to have a command
> that checks for the existence of an executable by some name, and to
> refuse to continue if this command fails.

I haven't really followed why all this complexity with the multiple  
scheme ports is required -- I realize you tried to spell it out in  
your first email but it was a bit much for me at the moment.

But assuming it really is required, then yes, this is the method that  
occurred to me as well: just test for the file's existence in, say,  
the pre-fetch phase, and fail if not found. I don't, however, know  
the portfile syntax for checking for a file's existence.

> There was some recent
> discussion about a `ui_fatal' command by which to fail, although I
> understand that it was simply a proposal not yet implemented.  Does
> this sound plausible, however?

Not really needed, though, either. Just do ui_error "the message"  
followed by exit 1. And, again, do this in the pre-fetch phase.