New Lagged Fib. PRNG gen and random2.d

[Joseph Rushton Wakeling]

On 26/08/13 11:24, monarch_dodra wrote:
> However, it can *also* generate ulongs with 64 bits of randomness, but doing so
> only takes roughly 40% more time. Which is great? I'd have to bench on a linux
> 64 with a dmd64 compiler: I think a true 64 bit implementation should have even
> less overhead, making LF *faster* (!) than MinstdRand0.

I'll try and benchmark that myself.  Boost also defines a 64-bit Mersenne 
Twister which we really should have in Phobos; it'll require some tweaks to the 
MersenneTwisterEngine design (some more template parameters).