Using libxml++ in classes

Question

I am trying to write a class to parse XML documents. This is the header file:

using namespace std;
class xmlHelper {
public:
    xmlHelper();
    virtual ~xmlHelper();

private:
    xmlpp::DomParser parser;
    };

The code looks like this:

#include "xmlHelper.h"

xmlHelper::xmlHelper()
{

}
xmlHelper::~xmlHelper() 
{

}

Compiling fails with these errors:

error: use of deleted function ‘xmlHelper::xmlHelper(const       xmlHelper&)’ 
error: use of deleted function ‘xmlpp::Parser::Parser(const xmlpp::Parser&)’ 
error: use of deleted function ‘xmlpp::NonCopyable::NonCopyable(const xmlpp::NonCopyable&)’

Moving the line xmlpp::DomParser parser; from the header file to the constructor, the code compiles. I want to use a private variable which holds the XML document. What do I have to do to create such a variable?

Thx

Answer 1

Your class is probably being copied somewhere (std::vector containee perhaps?) and the xmlpp::Parser object does not allow copying.

When you have a class that allows copying/moving, all the members inside the class have to have non-deleted copy/move constructors or operator =s (either default or explicitly defined, but not deleted).

Use std::shared_ptr<xmlpp::Parser> instead.