View source for Deque.popback

== Calling Pattern ==
Call
 local d = sl.deque()
 -- later
 local r = d.popback()
Results
 r is any type

== Description ==

Calling popback returns the value at the front of the queue and removes it.  If the queue is empty, popback returns nil.

== Upon Error ==

Errors are reported and handled according to the operant error redirection mode.

== See Also ==

* [http://www.easyuo.com/openeuo/wiki/index.php/Simplelib simplelib]

* [[deque]]
* [[deque.popfront]]