RosettaCodeData/Task/Queue-Usage/REBOL/queue-usage.rebol

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; Create and populate a FIFO:
q: make fifo []
q/push 'a
q/push 2
q/push USD$12.34 ; Did I mention that REBOL has 'money!' datatype?
q/push [Athos Porthos Aramis] ; List elements pushed on one by one.
q/push [[Huey Dewey Lewey]] ; This list is preserved as a list.
; Dump it out, with narrative:
print rejoin ["Queue is " either q/empty [""]["not "] "empty."]
while [not q/empty][print [" " q/pop]]
print rejoin ["Queue is " either q/empty [""]["not "] "empty."]
print ["Trying to pop an empty queue yields:" q/pop]