    "An error that occurs due to an incorrectly written program.
     An instance is thrown when an assertion fails, that is,
     when a condition in an `assert` statement evaluates to
     false at runtime.

     The assertion

         \"x must be positive\"
         assert (x>0);

     has almost the same effect as this `if` statement

         if (!x>0) {
             throw AssertionError(\"x must be positive\");
         }"
    shared native class AssertionError(message)
            extends Throwable(message) {
        "A message describing the assertion that failed. In the
         case of an `assert` statement, it is the text specified
         by the `doc` annotation.

         Certain tools interpret this message as
         markdown-formatted text."
        String message;
    }