Hello Ulf, Ulf Herrman <strin...@tilde.club> writes:
> #:deep? #t currently works by interposing a dummy build system that > lowers the package to a bag using the original build system, then > applies the supplied transformation to all of the bag's inputs, then > returns a new bag with the new inputs. > > The problem with this approach is that it doesn't affect the bag > arguments. This means that packages passed in as arguments may still > end up being used without being transformed. Worse still, packages > *not* passed in as arguments may end up being used *unless one is > explicitly passed in as an argument*, as is the case with > qt-build-system's #:qtbase argument. > > In short, the current approach of having the build-system lower > procedure leave the arguments mostly unchanged and letting the > bag->derivation procedure (the "bag builder") fill in lots of defaults > means that there are implicit inputs that cannot be touched at the > package level without adding special logic for every single build system > that does something like this. This is indeed sub-optimal! > I propose that we have the build system lower procedure (that is, the > one that converts from package to bag) completely fill in the argument > list with all defaults, and we modify build-system-with-package-mapping > to transform all arguments that look like a package or a list of > packages (or maybe even a tree containing packages). [...] > What do you think? Like Csepp, I like your proposition! I'm CC'ing the core team, in case they have something to add to it, but otherwise, we only need a volunteer to turn it into code :-). -- Thanks, Maxim