		       G N A T   E X A M P L E S
		       =========================

The projects in this directory illustrates a more elaborate project
organization:

* main.gpr contains some variable definitions
* full1.gpr is a first project that uses these definitions
* full2.gpr is a second project that uses these definiitions.

One interesting feature, besides the 'with' mechanism, is the external
variable mechanism, which makes possible defining from outside the
project file a variable which is used inside.

In our case, the projects use an external variable named 'BUILD' which
can be used to change some optimization and some directories. The default
value for BUILD is "debug", but alternatives include "release" and 
"release_optimized"

The first way to change the value of BUILD is to use an environment 
variable:

  $ export BUILD=release
  $ gnatmake -P full1.gpr
  $ gnatmale -P full2.gpr

The second way to change this variable is to use the -X switch of
gnatmake

  $ gnatmake -XBUILD=release_optimized -P full1.gpr
  $ gnatmake -XBUILD=release_optimized -P full2.gpr
