C++ boost mpl vector
- by Gokul
I understand that the following code won't work, as i is a runtime parameter and not a compile time parameter. But i want to know, whether there is a way to achieve the same. i have a list of classes and i need to call a template function, with each of these classes.
void
GucTable::refreshSessionParams()
{
typedef boost::mpl::vector< SessionXactDetails, SessionSchemaInfo > SessionParams;
for( int i = 0; i < boost::mpl::size<SessionParams>::value; ++i )
boost::mpl::at<SessionParams, i>::type* sparam =
g_getSessionParam< boost::mpl::at<SessionParams, i>::type >();
sparam->updateFromGucTable(this);
}
}
Can someone suggest me a easy and elegant way to perform the same? i need to iterate through the mpl::vector and use the type to call a global function and then use that parameter to do some run-time operations.
Thanks in advance,
Gokul.
Working code
typedef boost::mpl::vector< SessionXactDetails, SessionSchemaInfo > SessionParams;
class GucSessionIterator
{
private:
GucTable& m_table;
public:
GucSessionIterator(GucTable& table)
:m_table(table)
{
}
template< typename U > void operator()(const U& )
{
g_getSessionParam<U>()->updateFromGucTable(m_table);
}
};
void
GucTable::refreshSessionParams()
{
boost::mpl::for_each< SessionParams >( GucSessionIterator(*this) );
return;
}
