Variable arguments with file and line information?

[bearophile]

Namespace:

> It is always surprising how quickly one has found its own 
> solution, after you have posted here... :)

This is a well known psychological phenomenon: when you explain 
your problem to other people you lay down the problem very well, 
its constraints, its invariants, your needs, and this helps a lot 
the problem-solving parts of your mind find a solution :-)

This phenomenon is so strong, that some researchers assume to 
know a topic well enough only after they have taught one class 
about it :-)

That's why keeping a "laboratory notebook" for your programming 
activities, where you write down and explain what you do and what 
you have done, helps solve your problems. Unfortunately many 
computer science teachers don't explain their students why and 
how to keep such notebook.

Bye,
bearophile