Hi, I am testing "stuff" in a loop, and the "failure message" from Boost.Test is not too useful, because it does not tell me the "loop variable" value. I have hit this "problem" several times already, not only in loops, but any times a variable is involved in a tested expression. And I was not able to figure out what to do. I've looked at the sources etc., but I am too stupid to see if there is a solution in there. I haven't seen anything in the documentation. :( Imagine this: BOOST_CHECK_EQUAL(cont.erase(key),1u); If it fails, it tells me this: basics.cpp(61): error in "test_case": check cont.erase(key) == 1u failed [0 != 1] I cannot see the value of the 'key' variable, so it quite hard to know what that error is. In case of simple code, it may not be a problem to track down what key is, but when it is a loop of over 100000 iterations... :( ..._CHECKPOINT does not work, because it is only printed in case of an exception, but not other failures. :( I was hoping to find something like: BOOST_CHECK_EQUAL_WITH(cont.erase(key),1u, (key) ); which would say: basics.cpp(61): error in "test_case": check cont.erase(key) == 1u failed [0 != 1] with key == 12 Is there a way I could do that? I have tried to ask in #BOOST on IRC, but it seems there are only bots there. :( TIA, Attila