Functional, Functional-Shared, Prototypal, Pseudoclassical implementations of Stacks and Queues in JavaScript

stackNqueues.js

/******************************************************/
/******************************************************/
/**
 * FUNCTIONAL QUEUE
 */

/** Queues are FIFO, first in first out */
'use strict';
var makeQueue = function() {

    //GLOBALS
    /** @type {Object} our storage object for our queue */
    var storage = {};
    var length = 0; //keep track of queue length

    /** @type {Object} basic queue */
    var queue = {

        enqueue: function(value) {
            storage[length] = value;
            length++;
            return this;
        },

        dequeue: function() {
            var fifo = storage[0];
            if (length > 0) {
                for (var i = 0; i < length; i++)
                    storage[i] = storage[i + 1];
                length--;
            }
            return fifo;
        },

        size: function() {
            return length;
        },

        viewQueue: function() {
            return storage;
        }

    };
    return queue;
}

var queue = makeQueue();
queue.enqueue('a');
queue.enqueue('b');
console.log(queue.dequeue());
console.log(queue.viewQueue());
queue.enqueue('c');
console.log(queue.viewQueue());
console.log(queue.dequeue());



/**
 * FUNCTIONAL STACK
 */

/** Stacks are LIFO, last in first out */
var makeStack = function() {
    var storage = {};
    var length = 0;

    var stack = {

        push: function(value) {
            storage[length] = value;
            length++;
        },

        pop: function() {
            /** get last  value in storage */
            if (length > 0) {
                var result = storage[length - 1];
                delete storage[length - 1];
                length--;
            }
            return result;
        },

        size: function() {
            return length;
        },

        view: function() {
            return storage;
        }
    };

    return stack;

};

var stack = makeStack();

stack.push('a');
stack.push('b');
stack.push('c');
console.log(stack.view());
stack.pop();
stack.pop();
stack.pop();
console.log(stack.pop());

/******************************************************/
/******************************************************/

/**
 * FUNCTIONAL-SHARED QUEUE
 */

var makeQueue = function() {

    var queue = {
        storage: {},
        _size: 0
    };

    extend(queue, queueMethods);

    return queue;
};


function extend(obj1, obj2) {
    for (var key in obj2)
        obj1[key] = obj2[key];
}


var queueMethods = {

    enqueue: function(value) {
        this.storage[this._size] = value;
        this._size++;
    },

    dequeue: function() {
        var result = this.storage[0];
        if (this._size > 0) {
            for (var i = 0; i < this._size; i++)
                this.storage[i] = this.storage[i + 1];
            this._size--;
        }
        return result;
    },

    size: function() {
        return this._size;
    },

    view: function() {
        return this.storage;
    }

};


var queue = makeQueue();
for (var i = 0, rnd; i < 100; i++) {
    rnd = Math.floor((Math.random() * (123 - 97)) + 97);
    queue.enqueue(String.fromCharCode(rnd));
}
console.log(queue.view());
console.log('D: ' + queue.dequeue());
console.log('D: ' + queue.dequeue());
console.log(queue.view());

/**
 * FUNCTIONAL-SHARED STACK
 */

var makeStack = function() {

    //intialize stack object
    var stack = {
        storage: {},
        _size: 0
    };
    //extend stack object
    extend(stack, stackMethods);
    return stack;
};

var stackMethods = {
    push: function(value) {
        this.storage[this._size] = value;
        this._size++;
    },
    pop: function() {
        var result = this.storage[this._size - 1];
        if (this._size > 0) {
            delete this.storage[this._size - 1];
            this._size--;
        }
        return result;
    },
    size: function() {
        return this._size;
    },

    view: function() {
        return this.storage;
    }
};


var stack = makeStack();
console.log(stack);
stack.push(10);
stack.push(10);
stack.push(10);
stack.push(10);
console.log(stack.view());
stack.pop();
stack.pop();
console.log(stack.view());