Stack and Queue

The Stack and Queue types are a light-weight wrapper of a deque type, which respectively provide interfaces for LIFO and FIFO access.

Usage of Stack:

s = Stack{Int}()
push!(s, x)
x = top(s)
x = pop!(s)

Usage of Queue:

q = Queue{Int}()
enqueue!(q, x)
x = front(q)
x = back(q)
x = dequeue!(q)

Both Stack and Queue implement the Iterator interface; iterating over Stack returns items in FILO order and iterating over Queue returns items in FIFO order. There is also a reverse_iter function implemented for both which returns items in the reverse order for each type (i.e. FIFO for Stack and LIFO for Queue).