Re: Can I get a ptr to an element from an stl vector iterator?

From:

red floyd <redfloyd@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Fri, 26 Dec 2008 11:36:02 -0800 (PST)

Message-ID:

<f9a2314c-7848-436e-a22e-51433419f6b5@e22g2000vbe.googlegroups.com>

On Dec 26, 1:53 am, Kai-Uwe Bux <jkherci...@gmx.net> wrote:

Steve555 wrote:

Hi,

Given a struct:

struct myStruct{
int a;
float b;
};

and given a vector containing them, how do I get a ptr to one while
iterating through that vector:

myStruct *myStructPtr;
vector<myStruct>::iterator iter;
for(iter = myStructVec.begin(); iter != myStructVec.end(); ++ iter)
{
        myStructPtr = iter; (???
       ChangeStructValuesFunction( myStructPtr );
       ...
}

You can obtain a pointer by taking the address of the pointee:

myStructPtr = &*iter;

The goal is to modify a & b in-place.

If that is the goal, the signature of ChangeStructValuesFunction() should
be:

ChangeStructValuesFunction( myStruct & my_struct );

Then, you could just do:

ChangeStructValuesFunction( *iter );

always assuming, of course, that myStruct hasn't redefined operator&.

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