make-random-state {&optional state} => new-state
state---a random state, or nil, or t. The default is nil.
new-state---a random state object.
Creates a fresh object of type random-state suitable for use as the value of *random-state*.
If state is a random state object, the new-state is a copy_5 of that object. If state is nil, the new-state is a copy_5 of the current random state. If state is t, the new-state is a fresh random state object that has been randomly initialized by some means.
(let* ((rs1 (make-random-state nil))
(rs2 (make-random-state t))
(rs3 (make-random-state rs2))
(rs4 nil))
(list (loop for i from 1 to 10
collect (random 100)
when (= i 5)
do (setq rs4 (make-random-state)))
(loop for i from 1 to 10 collect (random 100 rs1))
(loop for i from 1 to 10 collect (random 100 rs2))
(loop for i from 1 to 10 collect (random 100 rs3))
(loop for i from 1 to 10 collect (random 100 rs4))))
=> ((29 25 72 57 55 68 24 35 54 65)
(29 25 72 57 55 68 24 35 54 65)
(93 85 53 99 58 62 2 23 23 59)
(93 85 53 99 58 62 2 23 23 59)
(68 24 35 54 65 54 55 50 59 49))
Should signal an error of type type-error if state is not a random state, or nil, or t.
section random [Function] , section random-state [System Class]
One important use of make-random-state is to allow the same series of pseudo-random numbers to be generated many times within a single program.
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