*random-state*

∗random-state∗ Variable

Value Type:

a random state.

Initial Value:

implementation-dependent.

Description:

The current random state, which is used, for example, by the function random when a random state is not explicitly supplied.

Examples:

(random-state-p \*random-state\*) → true 
(setq snap-shot (make-random-state)) 
;; The series from any given point is random, 
;; but if you backtrack to that point, you get the same series. 
(list (loop for i from 1 to 10 collect (random)) 
      (let ((\*random-state\* snap-shot)) 
	(loop for i from 1 to 10 collect (random))) 
      (loop for i from 1 to 10 collect (random)) 
      (let ((\*random-state\* snap-shot)) 
	(loop for i from 1 to 10 collect (random)))) 
→ ((19 16 44 19 96 15 76 96 13 61) 
   (19 16 44 19 96 15 76 96 13 61) 
   (16 67 0 43 70 79 58 5 63 50) 
   (16 67 0 43 70 79 58 5 63 50)) 

Affected By:

The implementation.

random.

See Also:

make-random-state, random, random-state

Notes:

Binding *random-state* to a different random state object correctly saves and restores the old random state object.

Expanded Reference: *random-state*

tip

TODO: Please contribute to this page by adding explanations and examples

*random-state*