Re: [boost] [modularization] proposal and poll

Subject: Re: [boost] [modularization] proposal and poll
From: Nat Goodspeed (nat_at_[hidden])
Date: 2014-05-30 09:01:26

On Fri, May 30, 2014 at 8:31 AM, Peter Dimov <lists_at_[hidden]> wrote:

> Glen Fernandes wrote:

>> It would be nice if both approaches (static configuration, automatic
>> identification) take into account - or allow you to specify - conditional
>> dependencies (e.g. dependencies based on identification of supported or
>> unsupported features determined by Boost.Config).

> It would be nice, but is it implementable? How could the dependency tracker
> determine what Boost.Config will define?

I've been assuming that Julian's proposal will require, at least
initially, that someone (the library maintainer, an interested
volunteer) manually edit a specification in some syntax of the other
libraries on which this one directly depends. That information could
be informed by, but need not be identical to, the output of a tool.

In that case, Glen's suggestion only requires that the specification
syntax include some way of annotating each dependency: "only for the
following toolsets..."

It may also be possible to write a (wave-based?) tool that analyzes
the preprocessor conditions under which each #include is reached, but
I see that as very much a separable (and deferrable) effort.