Re: VS 2008

From:
DanB <abc@some.net>
Newsgroups:
microsoft.public.vc.mfc
Date:
Fri, 26 Feb 2010 17:25:35 -0700
Message-ID:
<4EZhn.891$cI.225@newsfe24.iad>
Giovanni Dicanio wrote:

"DanB" <abc@some.net> ha scritto nel messaggio
news:x9Yhn.5035$mn6.401@newsfe07.iad...

class HE_XML_EXT_CLASS XMLNODESET
{
private:
std::vector<TiXmlNode*> set;
...
};

The pointer to the vector is copied now where as in 7.1 it would do a
deep copy of the vector.


I'm not sure that deep-copying the above 'set' data member is a good
robust thing, because the pointers stored in the vector are copied.
What is the semantics of 'set'? Does the XMLNODESET class "own" the
pointed TiXmlNode's?
In this case, I would prefer using something like:

vector< shared_ptr< TiXmlNode > > set;

Giovanni


Thank you Giovanni, David.

The const qualifier did no fix this.

Yes, the copy is not deep, only the pointer set needs to be copied, not
what they point at.

The copy constructor itself is implicit. I'm returning the object from a
function call, like:

XMLNODESET CXML::GetNodeSet( LPCTSTR xpattern )
{
    XMLNODESET set( this );

//note that 'this' in this case is the CXML object and why there is no
public constructor for XMLNODESET. You can only get XMLNODESETs from CXML.

    if( xpattern == NULL )
        return set;

    CXPath xparse( documentNode->RootElement( ), currentNode, xpattern );
    lastXPathError= xparse.GetError( );
    lastXPathCount= xparse.GetCount( );

    for( unsigned long i= 0; i < xparse.GetCount( ); ++i )
        set.set.push_back( xparse.GetNode( i ) );

    return set;
}

XMLNODESET is little used and small so didn't see a reason to return a
pointer to one of them. Also, this call is in a dll and in the app
called like:

nodeset= xml.GetNodeSet( "//*/subStuff/testing[@type=1]" );

But like I say, it works fine in 7.1. I get a fresh separate copy of the
vector.

Thanks, Dan.

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