I found this line of a code in a class which I have to modify:
::Configuration * tmpCo = m_configurationDB;//pointer to current db
and I don’t know what exactly means the double colon prepended to the class name. Without that I would read: declaration of tmpCo
as a pointer to an object of the class Configuration
… but the prepended double colon confuses me.
I also found:
typedef ::config::set ConfigSet;
9 s
This ensures that resolution occurs from the global namespace, instead of starting at the namespace you’re currently in. For instance, if you had two different classes called Configuration
as such:
class Configuration; // class 1, in global namespace
namespace MyApp
{
class Configuration; // class 2, different from class 1
function blah()
{
// resolves to MyApp::Configuration, class 2
Configuration::doStuff(...)
// resolves to top-level Configuration, class 1
::Configuration::doStuff(...)
}
}
Basically, it allows you to traverse up to the global namespace since your name might get clobbered by a new definition inside another namespace, in this case MyApp
.