Re: [Boost-build] Default action is "install" ??

From: Vladimir Prus (ghost_at_[hidden])
Date: 2006-11-18 12:43:13

On Saturday 18 November 2006 00:53, Rene Rivera wrote:
> Vladimir Prus wrote:
> > On Thursday 16 November 2006 03:28, Rene Rivera wrote:
> >> I just tried, in HEAD:
> >>
> >> cd boost-root
> >> bjam --v2 -n toolset=gcc --with-thread
> >>
> >> I was expecting it to *only* *build* the thread library. Instead, after
> >> complaining that it can't build some targets, it builds and installs the
> >> thread library plus all the headers. Neither "stage" nor "install"
> >> should be implicit in any form. This is not only different from what
> >> BBv1 does, but is also against what an autoconf "make" does which is
> >> what we are trying to model as far as build+install goes.
> >
> > I think one 'explicit' should help ;-)
>
> Of course :-) But that reminds me...
>
> I've been thinking of how we set the implicit vs. explicit, as compared
> to other attributes. Something that Dave drove into me from the design
> of BBv1 is that we really want to stick to using declarative
> formulations. And the "explicit <target> ;" just doesn't look
> declarative to me, since it's detached from the target declaration :-)
> So I had an idea last night while working on some non-boost jamfiles and
> thinking about the <build>no functionality. Why not merge the
> explicit/implicit aspect with the build aspect? They both control the
> functionality, just different options for building. We would have:
>
>    feature build : implicit explicit no ;
>
> That splits current "<build>yes" into what we actually have of implicit
> vs. explicit building. This way we can do the more convenient of setting
> "<build>explicit" at the project level, and then be able to select
> specific targets to <build>implicit.

I'm afraid this won't place nice with target alternatives:

        obj foo : foo_msvc.c : <toolset>msvc ;
        obj foo : foo_gcc.c : <toolset>gcc ;
        explicit foo ;

To make 'explicit' a value of a 'build' property, you'd have to duplicate it.

- Volodya