Re: Pointer to STL element address?

From:
James Kanze <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Mon, 25 May 2009 13:40:43 -0700 (PDT)
Message-ID:
<b006662c-5100-4498-aad2-00dada777673@m17g2000vbi.googlegroups.com>
On May 25, 5:42 pm, Michael <comtech....@gmail.com> wrote:

On May 25, 8:33 am, p...@informatimago.com (Pascal J.
Bourguignon) wrote:

Michael <comtech....@gmail.com> writes:

In the following STL insertion, how do I maintain a pointer pointing
to the address of that element being inserted?


http://www.cplusplus.com/reference/stl/

my_list.push_back(my_element);


std::list<YourElementType>::iterator pointer=my_list.end()-1;

my_map[key]=my_element;


std::map<YourKeyType,YourElementType>::iterator pointer=my_map.find(k=

ey);

Can this iterator be used as a normal C++ pointer?


Not in all cases. It can be used as a normal C++ pointer in
certain cases.

my_map.find actually wastes some time.

Is there a way, when my_map inserts the element, I can get its
address as a pointer, instead of doing a "find" after
insertion?


Use map<>::insert.

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