Re: Conditional append

[J.T. Conklin]

Shaun Jackman <address@hidden> writes:
> Thanks Stepan. I'm going to go with your latter suggestion, since it
> doesn't require modifying all the other Makefile.am. This seems like a
> rather arbitrary limitation of automake though. Is there any reason
> why the append operator shouldn't treat an undefined variable as
> empty?

I wish it would.  IMO, the current behavior violates the principal of
least surprise.

ACE & TAO use MPC (Make Project Creator) to generate Makefile's,
Makefile.am's, MSVC++ project files, etc. from a common set of *.mpc
files.  MPC's automake module has a lot of otherwise unecessary code
to track whether a given automake principal has been output in order
to use "=" or "+=".  

All that cruft could be removed if automake interpreted "+=" of a
previously unseen variable as an assignment.

    --jtc

-- 
J.T. Conklin