I'm using the myAssert() suggested by others in the D forum, with a few tweaks:

void myAssert(int line = __LINE__, string file = __FILE__, Args...)(lazy bool condition, lazy Args args) {

  string string_version_of_condition = //? how?
  if (!condition)
    {
      writefln("Assertion (%s) failed @ %s:%d in test '%s'",
      string_version_of_condition, file, line, currentTestName);
      foreach(a; args) {
        write("   assert-extra: ");
        writeln(a);
      }
      exit(1);
    }
  }
}

This is great, but I would also like to print out the stringified version of the condition, so that the assert shows me the text of the failed test-condition.

e.g.

myAssert(1 == 0);

// should result in:

Assertion (1 == 0) failed @ test.d:34 in test 'bool test'

How to I initialize string_version_of_condition?  In C/C++, I'd use a macro and token pasting.