Re: references and pointers

From:
"Jim Langston" <tazmaster@rocketmail.com>
Newsgroups:
comp.lang.c++
Date:
Sat, 3 Nov 2007 22:52:26 -0700
Message-ID:
<%4dXi.728$lH1.579@newsfe06.lga>
"Ian Collins" <ian-news@hotmail.com> wrote in message
news:5p4rqvFp7vuvU11@mid.individual.net...

borophyll@gmail.com wrote:

On Nov 4, 12:00 pm, Ian Collins <ian-n...@hotmail.com> wrote:

boroph...@gmail.com wrote:

Why then does Stroustrup make the following statement in his book:
"Be suspicious of non-const reference arguments; if you want the
function to modify its arguments, use pointers and value return
instead"

He made a mistake? Or possibly idiomatic style has changed over time.


*Please* don't quote signatures.

Are you serious? This is in the most recent version of "The C++
programming language", and he mentions this point in several
locations. Hardly an editing mistake. Let me just state that I am
not debating that the point he makes seems right, it does not seem
right to me, but it seems to be more than just a mistake.


http://www.research.att.com/~bs/bs_faq2.html#pointers-and-references

Puts a different view across, so one of my guesses was probably true.

I'd only recommend using pointers when the argument can meaningfully be
NULL, or when interfacing with legacy code.


I was actually debating this with myself 2 days ago. Someone gave me some
code work on, he was using pointers to modify the parameters. I started to
change them to references, then realized that in mainline, there is no
indication if the parameter was going to be changed or not.

Consider.

void foo( int* Val )
{
   *Val = 23;
}

void bar( int& Val )
{
   Val = 23;
}

int main()
{
   int MyInt = 10;
   foo( &MyInt );
   bar( MyInt );
}

Becaue Foo forces us to take the address of MyInt, it is fairly obvious in
mainline that MyInt is probably going to be changed, else why pass the
address of a simple int? bar however gives no indication in mainline that
MyInt will be changed.

Maybe that is the reasoning behind it.

Reguardless, I did go ahead and change them all to references anyway.

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