Functional Programming: Understand the Hazards of Using Imperative Code

finalTabs.tabs should be ['FB', 'Gitter', 'Reddit', 'Twitter', 'Medium', 'new tab', 'Netflix', 'YouTube', 'Vine', 'GMail', 'Work mail', 'Docs', 'freeCodeCamp', 'new tab']

I got an answer as shown below , but I am missing the word ‘Vine’ Would you be able to help me please.

[ ‘FB’,
‘new tab’,
‘Work mail’,
‘new tab’ ]

Here is my Code:

// tabs is an array of titles of each site open within the window

var Window = function(tabs) {

this.tabs = tabs; // We keep a record of the array inside the object


// When you join two windows into one window

Window.prototype.join = function (otherWindow) {

this.tabs = this.tabs.concat(otherWindow.tabs);

return this;


// When you open a new tab at the end

Window.prototype.tabOpen = function (tab) {

this.tabs.push(‘new tab’); // Let’s open a new tab for now

return this;


// When you close a tab

Window.prototype.tabClose = function (index) {

// Only change code below this line

var tabsBeforeIndex = this.tabs.splice(0, index); // Get the tabs before the tab

var tabsAfterIndex = this.tabs.splice(index); // Get the tabs after the tab

this.tabs = tabsBeforeIndex.concat(tabsAfterIndex); // Join them together

// Only change code above this line

return this;


// Let’s create three browser windows

var workWindow = new Window([‘GMail’, ‘Inbox’, ‘Work mail’, ‘Docs’, ‘freeCodeCamp’]); // Your mailbox, drive, and other work sites

var socialWindow = new Window([‘FB’, ‘Gitter’, ‘Reddit’, ‘Twitter’, ‘Medium’]); // Social sites

var videoWindow = new Window([‘Netflix’, ‘YouTube’, ‘Vimeo’, ‘Vine’]); // Entertainment sites

// Now perform the tab opening, closing, and other operations

var finalTabs = socialWindow

.tabOpen() // Open a new tab for cat memes

.join(videoWindow.tabClose(2)) // Close third tab in video window, and join



I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

Please use the “preformatted text” tool in the editor (</>) to add backticks around text.

See this post to find the backtick on your keyboard.
Note: Backticks are not single quotes.


For one you’re overwriting the Window object with:

var Window = function(tabs) {

Which should like never happen.

Thank you so much
It’s working now :grinning: