C++boost syntax – meaning of <>

I was generating a random number with the boost library, namely:

   boost::random::random_device rng;
   boost::random::uniform_int_distribution<> index_dist(0, chars.size() - 1);

Now I understand that uniform_int_distribution is class, but what’s the meaning of the empty <>? Is it a template?

>Solution :

It is indeed a template.
With no given datatype it will fall back to a default datatype to work with.

You can see that the default in this case is a regular int.

https://www.boost.org/doc/libs/1_51_0/doc/html/boost/random/uniform_int_distribution.html