Time complexity: O(1)
ACL categories: @read, @list, @fast
Returns the length of the list stored at
key does not exist, it is interpreted as an empty list and
0 is returned.
An error is returned when the value stored at
key is not a list.
Integer reply: the length of the list at
dragonfly> LPUSH mylist "World"
dragonfly> LPUSH mylist "Hello"
dragonfly> LLEN mylist