Vector set is a new data type that is currently in preview and may be subject to change.
VISMEMBER key element
Check if an element exists in a vector set.
keyis the name of the key that holds the vector set.
elementis the name of the element you want to check for membership.
0 if the element does not exist in the vector set, or the key does not exist. 1 if the element exists in the vector set.