SPOP

    Removes and returns one or more random members from the set value store at .

    This operation is similar to SRANDMEMBER, that returns one or more random elements from a set but does not remove it.

    When called without the count argument:

    Bulk string reply: the removed member, or nil when key does not exist.

    : the removed members, or an empty array when key does not exist.

    1. dragonfly> SADD myset "one"
    3. dragonfly> SADD myset "two"
    4. (integer) 1
    5. dragonfly> SADD myset "three"
    6. dragonfly> SPOP myset
    7. "one"
    8. dragonfly> SMEMBERS myset
    9. 1) "three"
    10. 2) "two"
    12. (integer) 1
    13. dragonfly> SADD myset "five"
    14. (integer) 1
    15. 1) "three"
    16. 2) "two"
    17. 3) "four"
    18. dragonfly> SMEMBERS myset
    19. 1) "five"

    Note that this command is not suitable when you need a guaranteed uniform distribution of the returned elements. For more information about the algorithms used for , look up both the Knuth sampling and Floyd sampling algorithms.