Re: B-D on src package? (was: Re: Challenge from Julia's non-standard vendored openblas"64_"

[Ian Jackson <ijackson@chiark.greenend.org.uk>]

Johannes Schauer writes ("Re: B-D on src package? (was: Re: Challenge from Julia's non-standard vendored openblas"64_""):
> We have to think about a good syntax for the Build-Depends field
> which is able to express a build dependency on source packages
> unpacked to /usr/src

Can I make a radical suggestion that the package should expect the
source to be in ../src (or similar) rather than in /usr/src ?

I appreciate we usually do this stuff in buildds but there are other
environments or situations where it would be much nicer if the source
code were somewhere that could be writeable by an ordinary user.

In particular if A src-build-depends B, usually that means that A
compiles B in a funny way.  To do development work properly on A, it
is necessary to be constantly editing B.  Now probably A has an ad-hoc
way to point to a different B but that is fragile and annoying.

I can see few downsides from treating
    Build-Depends: src:foo:src
(or whatever) to mean "src:foo" unpacked in a directory ../src/foo
(or some suitable other prefix).

(It should not mean that "foo.dsc" et al are available anywhere - just
the unpacked version, as found from dpkg-source -x.)

Ian.