A Tausworthe random number generator

[terchestor]

On Tuesday, 21 January 2014 at 12:32:43 UTC, bearophile wrote:
> terchestor:
>
>> https://github.com/Terchestor/dlang/tree/Tausworthe-class
>>
>
>> /++
>> §§§ Tausworthe
>
> What's the purpose of those §? They add noise. If they aren't 
> necessary I suggest to remove them.
>
Well, a fantasy, but I wont keep it!
>
>> class Tausworthe ( I, F ) if ( __traits(isIntegral, I ) &&
>>                               __traits(isFloating, F ) )
>
> I suggest to not put spaces around ( ). And if you want also 
> remove the space after the class/functions name.

That's an old usage of mine.

> Perhaps you want to use a struct? The decision is important. 
> Are your methods all virtual?

Not a struc, I need a class.

>
>> {
>>    alias I integral_t;
>>    alias F floating_t;
>
> Today the syntax "alias Name = Foo;" is preferred.

I knew not. Do ypu mean: alias integral_t = I;

> In D code the use of "_t" as suffix for types is less common. 
> And perhaps it's better to use a starting upper case letter for 
> their name.

I forgot the Capital letter, but I like the trailing _t, like 
size_t.
>
>>    enum tauswortheConstFloat : floating_t
>>    {
>>        tau0 = 4294967296.0f
>
> Class/struct/Enum/Union names should start with an upper case 
> letter.
>
>
>>         tau1 = 4294967294,
>
> Perhaps that literal can end with a U.
>
>
>>   ~this( )
>>    { }
>
> No need for this.

Of course!

>
>>    void seed( integral_t seed_=1 )
>> ...
>>        auto s = seed_;
>
> In general annotate with enum/const/immutable all variables 
> that don't need to mutate.

I'd better put an assertion (or enforce?) to be sure seed won't 
be null, and give constantness to seed.

>>        integral_t fseed( const integral_t s_ )
>>        {
>>            return ( tauswortheConst.lgc * s_ ) & 
>> tauswortheConst.mask;
>>        }
>
> That's probably better annotated as pure nothrow.

OK.

>
>> }//§§==========END_CLASS::Tausworthe==========
>
> I suggest to reduce the amount of === in this code.

OK.

>
>> auto ?tausworthe0 = new Tausworthe!(ulong, double);
>
> While D supports Unicode identifiers, they are a often a pain 
> in the ass (this is a personal opinion), so perhaps you want to 
> kill them all.

Not sure. I'm experimenting a kind of tagging to easily 
distinguish nested functions (with greek phi) or temporaries. 
Perhaps not a so good idea, but i'll see if enhances the 
readability later.
>
>> //§§ __COPYRIGHT_NOTICE__
>
> I think there's a ddoc field syntax for the copyright in the 
> module ddoc.

Yes, but it's a work on progress...
>

Thank you so much for your invaluable help.