Ownership/delete'ing the facet in a locale (std::locale)
I wrote the following function to get a date/time string using boost.date_time.
namespace bpt = boost::posix_time;
string
get_date_time_string(bpt::ptime time)
{
bpt::time_facet * facet(new bpt::time_facet);
facet->format("%Y%m%d%H%M%S");
stringstream return_value;
return_value.imbue(std::locale(std::locale::classic(), facet));
return_value << time;
return return_value.str();
}
I had a quick question about the ownership/ delete 'ing of the facet object. std::locale's constructor is not explicit on the ownership/ delete 'ing of the facet . Tried using shared_ptr -wrapped and stack allocated versions of facet - both of which caused seg-faults. Also, running the above function through valgrind didn't show any leaks(which probably implies that the locale or stream is taking care of delete 'ing), but I just wanted to be clear that I am doing the right thing here. Thanks.
According to Stroustrup, a 0 argument passed to the constructor tells the facet that the locale will handle destruction, and the both constructors of bpt::time_facet default to 0 when it isn't supplied. A non-zero value, though, implies that the programmer must explicitly handle the destruction of the facet .
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