Re: pointer in queue

From:
Kai-Uwe Bux <jkherciueh@gmx.net>
Newsgroups:
comp.lang.c++
Date:
Mon, 02 Feb 2009 10:38:47 +0100
Message-ID:
<gm6epb$814$2@news.doubleSlash.org>
James Kanze wrote:

On Feb 2, 10:07 am, Kai-Uwe Bux <jkherci...@gmx.net> wrote:

Ian Collins wrote:

Carl Forsman wrote:

I have a deque object.

Can I insert pointers into the queue? (I heard I cannot
insert pointer into a queue)

like this:
===============
std::deque < Sock* > * socks;
socks = new deque< Sock* >;


Why use new here?

int port = 4322;

for ( int i = 0; i< 10; i++ ) {
Sock * sock = new Sock();
sock->Create1(this, port);
socks->push_back(sock);
}

later I will loop the queue of socket:
===============
for ( std::deque<Sock>::const_iterator iter = socks->begin(); iter !=
socks->end(); iter++ ) {


for ( std::deque<Sock*>::const_iterator iter = socks->begin();
  iter != socks->end(); ++iter ) {

Sock temp = iter->first; // get the 1st socket


A deque iterator does not have a member first.

Unless you want to copy the object, you would require:

const Sock& temp = **iter;

Note the use of const reference. *iter is a Sock*.


Just a nit: the const is optional and might cause trouble.


What sort of trouble?


Inside the loop

  temp.some_non_const_method();

would not compile.

[snip]

Best

Kai-Uwe Bux

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