If you define the symbol boost_quaternions_TEST_VERBOSE, you will get additional
output (verbose output);
this will only be helpfull if you enable message output at the same time,
of course (by uncommenting the relevant line in the test or by adding
to your command line,...). In that case, and if you are running interactively,
you may in addition define the symbol BOOST_INTERACTIVE_TEST_INPUT_ITERATOR
to interactively test the input operator with input of your choice from the
standard input (instead of hard-coding it in the test).