--- Oliver Kullmann <O.Kullmann@Swansea.ac.uk> wrote:
The problem with the "very quick start" is, that without already understanding the architecture of the library it seems impossible to understand it.
Actually, there was a major change in the library architecture between boost versions 1.30 and 1.31. The change had to do with conformance to the WG21 specification, available at this link:
aha, thanks for the link; I was aware only of the general Technical Report on Standard Library Extensions (Draft), which I found actually more helpful than the Boost documentation.
boost::variate_generator<BaseRNG&,UniformDist> your_generator(rng, dist);
Note the ampersand; your program will fail silently if you omit it.
I don't understand the need for the reference type --- otherwise the object rng would be copied, which should also be alright?!
Nope. Without the reference type, a call like:
int random_number = your_generator();
would invoke the constructor instead of the () member operator; hence, the silent failure.
I don't understand this. According to the draft (N1648, available at http://anubis.dkuug.dk/jtc1/sc22/wg21/docs/papers/2004/#post_sydney) section 5.1.3, just using a non-reference type BaseRNG should work.
Perhaps one should emphasise, that models of pseudo-random generators are models of uniform random generators,
Yes, it says so in the concept documentation, which the reader is told to look at first, although the "emphasis" is rather weak, IMHO.
I just feel that the whole concept of "concepts" and "models" is not so easy to grasp, and thus I think it would be beneficial to say things several times.
and that also for example uniform_int yields a model of a uniform random generator.
Not quite. uniform_int models a uniform distribution over which random number generators should generate random numbers. variate_generator is the front-end number generator that applies the distribution constraint to the base random number generator.
In the draft, section 5.1.7.1 it says, that "a uniform_int random distribution satisfies all the requirements of a uniform number generator", and I guess that means that uniform_int is a model of a uniform random generator, or?!
Inclusion of something like the above explanations into the documentation would already help a lot!
Ideally, it would be so. The problem here is when Jens Maurer will find the time; presumably he's also working on improving the above-mentioned WG21 spec and preparing for the upcoming 1.32 release.
Of course; I just hope that this little e-mail stream might already help for some improvements (and every bit helps). Oliver