push-front ( deque item -- newdeque )
Persistent deques

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Vocabulary
persistent.deques

Inputs

deque	a deque
item	an object

Outputs

newdeque

a deque

Word description
Creates a new deque with the given object pushed onto the front side. This takes constant time.

Definition

USING: kernel persistent.deques.private ;

IN: persistent.deques

: push-front ( deque item -- newdeque ) swap push ;