Re: [boost] Re: random.hpp - suggestion for utility function

From: christopher diggins (cdiggins_at_[hidden])
Date: 2005-05-24 09:27:15

From: "Vladimir Prus" <ghost_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Tuesday, May 24, 2005 2:28 AM
Subject: [boost] Re: random.hpp - suggestion for utility function

> christopher diggins wrote:
>
>> AFAICT the shortest way to emulate the std::rand() function using
>> boost/random.hpp would be as follows:
>>
>>   unsigned int longhand_boost_rand() {
>>     boost::mt19937 rng;
>>     boost::uniform_int<> dist(0, RAND_MAX);
>>     boost::variate_generator
>>     <
>>       boost::mt19937,
>>       boost::uniform_int<>
>>     > generator(rng, dist);
>>     return generator();
>>   }
>>
>> (apologies if I made any mistakes)
>
> You can make it a bit shorter, I believe:
>
>   boost::mt19937 e;
>   return boost::uniform_int<>(0, 100)(e);
[snip]

Thanks you Vladmir and Michael for responding. So the correct shortest way 
would then have been simply to write:

unsigned int boost_rand() {
  static boost::mt19937 e;
  return boost::uniform_int<>(0, RAND_MAX)(e);
}

?

So the purpose of variate_generator only generates function objects? The 
introductory example http://www.boost.org/libs/random/ gives the impression 
that it is a neccessary step. I think the documentation then should be 
updated to be less confusing.

--
Christopher Diggins