The state of the generator.

The state must be seeded so that it is not everywhere zero. If you have a 64-bit seed, we suggest to seed a splitmix64 generator and use its output to fill s.

In Haskell, we've made this type opaque. See mkState to construct a State.

Create an initial state from a seed.

Raises an exception if the initial seed is all zeros.

>>> mkState 0 0 0 0
*** Exception: The state must be seeded so that it is not zero everywhere.
>>> mkState 1 2 3 4
mkState 1 2 3 4

This is xoshiro256** 1.0, our all-purpose, rock-solid generator. It has excellent (sub-ns) speed, a state (256 bits) that is large enough for any parallel application, and it passes all tests we are aware of.

For generating just floating-point numbers, xoshiro256+ is even faster.

>>> let state = mkState 1 2 3 4
>>> next state (\rand _state' -> rand)
11520

Note: When porting to Haskell, we've explicitly chosen to make the API of next in CPS-style (i.e., using a callback) to avoid always allocating a tuple for the result.

If you'd rather just have a tuple, you can pass (,) as the callback:

>>> next state (,)
(11520,mkState 7 0 262146 211106232532992)

This is the jump function for the generator. It is equivalent to 2^128 calls to next(); it can be used to generate 2^128 non-overlapping subsequences for parallel computations.

Note: This function is not yet implemented in Haskell.

This is the long-jump function for the generator. It is equivalent to 2^192 calls to next(); it can be used to generate 2^64 starting points, from each of which jump() will generate 2^64 non-overlapping subsequences for parallel distributed computations.

Note: This function is not yet implemented in Haskell.