Question

In a JavaScript code, I am trying to re-name an object by its stored data. I tried using pathTo as suggested by this site (http://thedesignspace.net/MT2archives/000381.html), but my console returns “ReferenceError: ‘pathTo’ is undefined”. My code looks something like this:

// This code defines the Object constructor Card, used to make the card objects
var Card = function() {
    this.face = theFace(this);
    this.suit = theSuit(this);
    this.value = theValue(this);
};

// This code creates the Deck to be used.
var deck = [];
for ( i=0 ; i<52 ; i++ ) {
    deck.push( i );
};
for ( i=51 ; i>0 ; i-- ) {
    var random = Math.floor(Math.random()*i);
    var temp = deck[random];
    deck[random] = deck[i];
    deck[i] = temp;
};
// 0-12 is Spades.
// 13-25 is Hearts.
// 26-38 is Clubs.
// 39-51 is Diamonds.

// Now we create the hand of the player and dealer
var player = [];
var dealer = [];

// Now to deal a card to player
player.push(deck.pop());
dealer.push(deck.pop());

// and another
player.push(deck.pop());
dealer.push(deck.pop());

// function theFace gives the face of a card
function theFace( card ) {
    var faces = ["King","Ace","2","3","4","5","6","7","8","9","10","Queen","Jack"];
    return(faces[card%13]);
};

// function theValue uses 'switch' to determine points from a card
function theValue(card) {
    var value = card % 13;
    switch( value ) {

        case(0):
        case(11):
        case(12):
            value = 10;
            break;

        case(1):
            value = 11;
            break;

        default:
            value = value;
            break;

    };
    return value;
};

// function theSuit returns the suit of a card
function theSuit(card) {
    var suit;
    if(card>38) {
        suit = "Diamonds";
    }else if(card>25) {
        suit = "Clubs";
    }else if(card>12) {
        suit = "Hearts";
    }else {
        suit = "Spades";
    };
    return suit;
};

// function toObject the first (numbered) card of of a hand 
// and turns it into an Object with the desired properties
function toObject( hand ) {
    var card = hand.shift();
    if (typeof(card) !== "number") {
        hand.unshift(card);
    } else {
        var card = new Card ();
        card = pathTo[card.suit + card.face];
    };
    return hand;
};

console.log(player);
toObject(player);
toObject(player);
console.log(player);

I am trying to rename the card I am turning from a typeof===”number” to typeof===”object” so that when I run the code multiple times (hence the function) I do not have duplicate names of the objects in the array of hands.

Here are some examples of what my console is printing:

[ 19, 46 ]
ReferenceError: 'pathTo' is undefined

and

[ 31, 18 ]
ReferenceError: 'pathTo' is undefined

There MUST be a way to do this, I just cannot find how.

In function toObject I am trying to take the first number(card) in the hand array and turn it into an object describing its qualifiers as a card of the standard 52 card deck. EDIT: I just realized I’m not even pushing it back. I am going to try something to see if it will work.

EDITEDITEDIT_SOLVED:
I have done it! It turns out that I don’t need to change the name, the code will keep it separate for me somehow. All I needed to do so that it runs correctly is this:

Replace

var Card = function() { 
    this.face = theFace(this); 
    this.suit = theSuit(this); 
    this.value = theValue(this); 
};

with

var Card = function(card) {
    this.face = theFace(card);
    this.suit = theSuit(card);
    this.value = theValue(card);
};

and

function toObject( hand ) {   
    var card = hand.shift();   
    if (typeof(card) !== "number") {   
        hand.unshift(card);   
    } else {   
        var card = new Card ();   
        card = pathTo[card.suit + card.face];   
    };   
    return hand;   
};

with

function toObject( hand ) {
    var card = hand.shift();
    if (typeof(card) !== "number") {
        hand.unshift(card);
    } else {
        var card = new Card (card);
        hand.push(card);
    };
    return hand;
};

Thanks for the help!

Answer 1

As @mattbornski points out, there is no pathTo object in JavaScript and, as far as I know, it’s not supported by any browser anywhere. That article seems to have omitted this part of their code.

Based on how you’re trying to use it, though, you’ll want to make a few changes to your code:

Create a pathTo object like this:

pathTo = {}; 

or

pathTo = new Object();

Then, give each new Card object a suit and face before you try to add it to pathTo (or before you try to use it to look up a card). For example, you could write:

myCard = new Card(23);

or

myCard = new Card('spade','2');

Finally, when your card has both a face and a suit, add it to the pathTo object like this:

pathTo[this.suit + this.face] = this; // use this inside the Card constructor

or

pathTo[myCard.suit + myCard.face] = myCard; // use this with an instance of a Card object

Then you can look up the cards with:

pathTo['spade2']