Priority Queue JavaScript Data Structure

PriorityQueue.js

//Queue Data Structure

function createQueue(){
    const q = [];
    return {
        //enque
        enque(item){
            return q.push(item);
        },
        //deque
        deque(item){
            return q.shift();
        },
        //peek
        peek(){
            return q[0];
        },
        //length
        get length(){
            return q.length;
        },
        //isEmpty
        isEmpty(){
            return q.length === 0
        }
    }
}

function createPriorityQueue(){

    const lowPriorityQueue = createQueue()
    const highPriorityQueue = createQueue()

    return {
        //enque
        enque(item, highPriority = false){
            highPriority ? highPriorityQueue.enque(item) : lowPriorityQueue.enque(item)
            return item;
        },
        //deque
        deque(){
            if(!highPriorityQueue.isEmpty()){
                return highPriorityQueue.deque()  
            }
            return lowPriorityQueue.deque();
        },
        //peek
        peek(){
            if(!highPriorityQueue.isEmpty()){
                return highPriorityQueue.peek()  
            }
            return lowPriorityQueue.peek();
        },
        //length
        get length(){
            return highPriorityQueue.length + lowPriorityQueue.length; 
        },
        //isEmpty
        isEmpty(){
            return highPriorityQueue.isEmpty() && lowPriorityQueue.isEmpty()
        }
    }
}