Queue with size limit.

If you push more elements onto the queue than it has room for, they will fall off screaming and wailing.

sized_queue(size)

Arguments

size	integer. Maximum number of elements in the queue.

Examples

not_run({
    q <- sized_queue(size = 2)
    q$push(1)
    q$get(1) # 1
    q$get(2) # NULL
    q$push(2)
    q$get(1) # 2
    q$get(2) # 1
    q$push(3)
    q$get(1) # 3
    q$get(2) # 2
    q$get(3) # NULL
})