Standard no-op output stream

Question

Is there a way to create an ostream instance which basically doesn\'t do anything ?

For example :

std::ostream dummyStream(...);
dummyStream <<         


        

Answer 1

If this is to disable logging output, your dummyStream would still cause arguments to be evaluated. If you want to minimize impact when logging is disabled, you can rely on a conditional, such as:

#define debugStream \
    if (debug_disabled) {} \
    else std::cerr

So if you have code like:

debugStream << "debugging output: " << foo() << std::endl;

No arguments will be evaluated if debug_disabled is true.