Re: Questionable advice
On Sunday, September 8, 2013 6:28:53 PM UTC+2, woodb...@gmail.com wrote:
I watched some of the videos from the C++ conference at
Microsoft. Some of the advice given was to not use raw
pointers for ownership. I think that's going too far.
http://webEbenezer.net/misc/SendBuffer.hh
http://webEbenezer.net/misc/SendBuffer.cc
Some of the advice was qualified with "outside of a managing class"
(or something like this). And even then you don't have to use raw
pointers for just managing memory. You're obviously targeting C++11
with your code and you could have just used unique_ptr<char[]> instead
of char* as type for the data member buf.
Someone may say that that doesn't scale if we need to
add another pointer to the class. I disagree. Classes
can have at least one pointer that isn't wrapped with
a smart pointer.
The more things a class has to keep track of, the more things can go
wrong. If you let your class manage more than one resource directly,
you're making your life possibly harder than it has to be.
Finally, at the conference STL pointed out that using a
delegated constructor you can safely have multiple raw
pointers in a class:
He did. He also said that he's not sure about what to think of that
approach. He certainly did not present it in a very positive light.
Previously I was using unique_ptr more than now, but
have found in each of these cases that the code that
results without using it so much is a little smaller.
You mean the compiled code? The binaries? Weird. I would not expect
that. I still don't.
I've seen a lot of overuse of shared_ptr over the years
and now think it's also possible to use unique_ptr too
much.
What makes you think so?
The simplified advice came from Bjarne. I think for
student programs it doesn't make much difference, but
he may be focussing too much on beginners these days.
The problem is that what one should and sould not do is not easily
put into a short word sequence. "no owning raw pointers" is an
approximation to that. It does require some explanation.
I would put this probably differently. "Delegate a resource management
problem to a class. Avoid writing classes that need to keep track of
too many things by breaking it into smaller classes". But it's not as
short as "no owning raw pointers". :-)
Cheers!
SG