Question

I am new to cpp (come from Java).
I am writing a cpp application. The application is performance critical.
i looked for a logging framework and i found log4cxx
at the end of the linked above there is performance section that explain:

When logging is turned off entirely or just for a set of levels, the
cost of a log request consists of a method invocation plus an integer
comparison

I remember from old days in university that we used then with #ifndf to wrap logging.

Questions:

1. Is wrapping logging with #ifndf is still standard practice?

2. Is there is something similar to the following pseudo-code?

logger.Log_Debug(() => { "My complicated log message " + thisFunctionTakesALongTime() + " will take no time" });

Answer 1

You can create your own macro that does nothing when in release mode:

#ifdef _DEBUG
#define LOG_DEBUG(x) logger.Log_Debug(x)
#else
#define LOG_DEBUG(x)
#endif