Ricardo Wurmus (2016-10-15 00:05 +0200) wrote:
> Hi Guix,
> it happened a couple of times already that a “substitute*” expression
> silently failed and I only found out about it when investigating the
> remains of a failing build (“guix build -K”). This can easily happen
> when a package is updated and substitutions “anchors” no longer exist in
> the updated source code.
> Would it be desirable to change “substitute*” (or replace it) such that
> it throws an error or returns a value if substitution failed? This
> might be helpful for the more complex packages with many substitutions.
> If we make it return a value (#f for error) it would also make our build
> phases a little prettier, I think. (Now we forcefully return #t in any
> case and that seems wrong.)
This was also discussed a bit around here:
As I mentioned in that message, I'm for returning #t/#f for