Python Datatype for a fixed-length FIFO

Question

I would like to know if there is a native datatype in Python that acts like a fixed-length FIFO buffer. For example, I want do create a length-5 FIFO buffer that is initial

Answer 1

x = collections.deque(5*[0], 5)

See the docs for more about collections.deque; the method you call push is actually called appendleft in that type.

The second parameter (maxlen, giving the maximum lengths) was added in Python 2.6; if you're using older versions of Python, it won't be available.

Answer 2

Just one more example to this post

from collections import deque

domains = ['1.com','2.com','3.com']
d = deque(domains)               
d.pop() #pop(delete) 3.com here
d.appendleft('new.com') 


print d

result:

deque(['new.com', '1.com', '2.com'])

Answer 3

you can also use list

a = [0,0,0,0,0]

a.pop(0)
a.append(1)

print a
result [0,0,0,0,1]

or for left side in right out, otherwise

a.pop(5)
a.insert(0,1)
print a
result [1,0,0,0,0]