Get Programming with JavaScript

Get Programming with JavaScript - Listing 4.10

Listing 4.10 - Calling the showMovieInfo function

var movie1;
var showMovieInfo;
var movie;

movie1 = {
    title: "Inside Out",
    actors: "Amy Poehler, Bill Hader",
    directors: "Pete Doctor, Ronaldo Del Carmen"
};

showMovieInfo = function () {
    console.log("Movie information for " + movie.title);
    console.log("------------------------------");
    console.log("Actors: " + movie.actors);
    console.log("Directors: " + movie.directors);
    console.log("------------------------------");
};

movie = movie1;

showMovieInfo();

Further Adventures

Listing 4.10 - Calling the showMovieInfo function - Task 1

Without declaring a movie2 variable, assign movie2 to the movie variable instead of movie1.

var movie1;
var showMovieInfo;
var movie;

movie1 = {
    title: "Inside Out",
    actors: "Amy Poehler, Bill Hader",
    directors: "Pete Doctor, Ronaldo Del Carmen"
};

showMovieInfo = function () {
    console.log("Movie information for " + movie.title);
    console.log("------------------------------");
    console.log("Actors: " + movie.actors);
    console.log("Directors: " + movie.directors);
    console.log("------------------------------");
};

movie = movie2;    // Assign movie2 to movie

showMovieInfo();

The movie2 variable has not been declared. An error will occur.

Listing 4.10 - Calling the showMovieInfo function - Task 2

Create an empty object and assign it to a movie2 variable.

var movie1;
var movie2;    // Declare a variable
var showMovieInfo;
var movie;

movie1 = {
    title: "Inside Out",
    actors: "Amy Poehler, Bill Hader",
    directors: "Pete Doctor, Ronaldo Del Carmen"
};

// Create an empty object
// Assign it to movie2
movie2 = {};

showMovieInfo = function () {
    console.log("Movie information for " + movie.title);
    console.log("------------------------------");
    console.log("Actors: " + movie.actors);
    console.log("Directors: " + movie.directors);
    console.log("------------------------------");
};

movie = movie2;

showMovieInfo();

The movie2 variable has been declared and assigned an empty object as a value. The title, actors and directors properties are undefined.

Listing 4.10 - Calling the showMovieInfo function - Task 3

Fill out movie2 with the properties needed by showMovieInfo.

var movie1;
var movie2;
var showMovieInfo;
var movie;

movie1 = {
    title: "Inside Out",
    actors: "Amy Poehler, Bill Hader",
    directors: "Pete Doctor, Ronaldo Del Carmen"
};

// Assign needed properties
movie2 = {
    title: "Tomorrowland",
    actors: "Britt Robertson, George Clooney",
    directors: "Brad Bird"
};

showMovieInfo = function () {
    console.log("Movie information for " + movie.title);
    console.log("------------------------------");
    console.log("Actors: " + movie.actors);
    console.log("Directors: " + movie.directors);
    console.log("------------------------------");
};

movie = movie2;

showMovieInfo();

The movie2 variable has been declared and assigned an object as a value. The title, actors and directors properties have been set and will be displayed.