Some questions about qdebug, a custom debug and const approach

[high_flyer]

but I dont understand you

I think so too
Your code is dangerous, because it assumes the caller of your operator is giving you an array which has "" at the end, I am not even talking about you not checking for a valid pointer 'data', but that is another issue.

Why don't use std::string or QString as input type?
It will make your code safer, and syntactically easier.

How can I know the end of << feeding

I answered that in my previous post.
You don't need to know.
Each operator<<() call takes one argument, and returns a value of some type which you call operator<<() again.
The call ends when all the object instances called their operator<<().

This line:

w_debug()<<"a word"<< data1<<"a word"<< data2;

w_debug()<<"a word"<< data1<<"a word"<< data2;

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Is the same as:

w_debug()<<"a word"; //return instance ofw _debug() on which the next call is done
w_debug()<<data1; //return instance of w_debug() on which the next call is done
w_debug()<<"a word";//return instance of w_debug() on which the next call is done
w_debug()<<data2;

w_debug()<<"a word"; //return instance ofw _debug() on which the next call is done
w_debug()<<data1; //return instance of w_debug() on which the next call is done
w_debug()<<"a word";//return instance of w_debug() on which the next call is done
w_debug()<<data2;

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