Re: [Boost-cmake] auto-modularization. Time to merge to main release branch?

From: David Abrahams (dave_at_[hidden])
Date: 2008-07-02 14:06:36

troy d. straszheim wrote:
> Saw some discussion on this...  here's the story.  I'll skip discussion
> of why one would want to do this at all :)
> 
> I believe this clears the way to check the cmake stuff in to the main
> release branch alongside everything else: everything can happily coexist
> with Boost.Build.   We no longer need to do any reshuffling of
> directories or adding svn:externals.  I suppose that could get
> political.  Thoughts?

Let's be brave.

> boost_library_project now takes an argument HEADERS, which lists the
> toplevel headers and subdirs relative to boost/ that are a part of this
> component.  eg:
> 
> boost_library_project(Signals
>   SRCDIRS src
>   TESTDIRS test
>   AUTHOR Doug Gregor
>   HEADERS signal.hpp signals.hpp signals
>   )
> 
> note that 'signals' above (the directory, not the header file) does
> *not* have a trailing slash.
> 
> The MODULAR keyword is GONE.  All libraries are considered modular
> all the time, that is if you depend on X, your include paths will always
> be appended with libs/X/include/boost.  

Great!

> Notice that these per-library
> include paths don't actually exist in svn: all of the headers are still
> 'in the monolith' toplevel boost/ directory (in fact, this directory is
> now an external pointing back to the 'main' release branch).   Things
> compile fine, since that directory is in the include path by default.
> 
> To 'automodularize' the boost tree, just
> 
>   make modularize
> 
> and those HEADERS from each library will get moved from toplevel boost/
> to each library's libs/*/include/boost directory.  This currently
> requires 'rsync' and 'rm' presumably working only unixy platforms,
> which should be fine, there's nothing about this that needs extensive
> special testing on windows.  Who knows, maybe under cygwin it would work.

I'm certain that it would; cygwin is POSIX.
Could you use something like python's shutil.copytree or
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/231501 to do
this portably?

-- 
Dave Abrahams
BoostPro Computing
http://www.boostpro.com