Write a warning to the log
LOG_WARN( LoggerPtr logger, EXPRESSION expression );
A pointer to a logger, which will have been retrieved using Logger::getLogger().
An expression that it is to be written to the log.
Any expression can be used that works as the right-hand-side of
os << expression where
os is of type
std::wostream under Unicode builds).
It can be a simple string, a number, or any object that supports the output stream
operator. The expression may include any number of items, each separated by a
For examples of use, see Using the logging macros.