Room 51 - GPWJ - Listing 10.09

Get Programming with JavaScript - Listing 10.09

Listing 10.09 - Functions to add and show exits


var Place = function (title) {
    this.title = title;
};

var kitchen = new Place("The Kitchen");
var dungeon = new Place("The Dungeon");

var exits = {};

var addExit = function (direction, place) {
    exits[direction] = place;
};

var showExits = function () {
    var keys = Object.keys(exits);

    keys.forEach(function (key) {
        console.log(key + " goes to " + exits[key].title);
    });
};

addExit("north", kitchen);
addExit("the trapdoor", dungeon);

showExits();

Further Adventures

Listing 10.09 - Functions to add and show exits - Tasks 1 & 2

Add a couple more places.
Use the addExit function to add exits to your new places.


var Place = function (title) {
    this.title = title;
};

var kitchen = new Place("The Kitchen");
var dungeon = new Place("The Dungeon");
var library = new Place("The Library");
var garden = new Place("The Garden");

var exits = {};

var addExit = function (direction, place) {
    exits[direction] = place;
};

var showExits = function () {
    var keys = Object.keys(exits);

    keys.forEach(function (key) {
        console.log(key + " goes to " + exits[key].title);
    });
};

addExit("north", kitchen);
addExit("the trapdoor", dungeon);
addExit("west", garden);
addExit("up the ladder", library);

showExits();

Listing 10.09 - Functions to add and show exits - Task 3

Update the showExits function so it only shows the directions, not the destinations.


var Place = function (title) {
    this.title = title;
};

var kitchen = new Place("The Kitchen");
var dungeon = new Place("The Dungeon");
var library = new Place("The Library");
var garden = new Place("The Garden");

var exits = {};

var addExit = function (direction, place) {
    exits[direction] = place;
};

var showExits = function () {
    var keys = Object.keys(exits);

    keys.forEach(function (key) {
        console.log(key);
    });
};

addExit("north", kitchen);
addExit("the trapdoor", dungeon);
addExit("west", garden);
addExit("up the ladder", library);

showExits();

Listing 10.09 - Functions to add and show exits - Task 4

Write a showDestination function that shows the destination when a direction is passed to it as an argument.


var Place = function (title) {
    this.title = title;
};

var kitchen = new Place("The Kitchen");
var dungeon = new Place("The Dungeon");
var library = new Place("The Library");
var garden = new Place("The Garden");

var exits = {};

var addExit = function (direction, place) {
    exits[direction] = place;
};

var showExits = function () {
    var keys = Object.keys(exits);

    keys.forEach(function (key) {
        console.log(key);
    });
};

var showDestination = function (direction) {
    console.log(direction + " leads to " + exits[direction]);
};

addExit("north", kitchen);
addExit("the trapdoor", dungeon);
addExit("west", garden);
addExit("up the ladder", library);

showExits();