[Question Regarding Named And Anonymous Funcitons Assigned To Variables]

Thank you both for the information. It is greatly appreciated! 

[Question Regarding Named And Anonymous Funcitons Assigned To Variables]

Let's see if I even got this right...

 

From what I understand, the following creates a named function and assigns it to a variable:
 

var someVar = function functionName() {
  //function body
};

 

And this creates an anonymous function assigned to a variable:

 

var someFunction = function() {
  //function body
};

 

What I don't understand is what the functional difference is between the two, so could someone please explain this to me?

[Chapter 6: Explicitely Defining Sparsely Populated Arrays And Conditions]

Thank you for clarifying. I guess I was somewhat confused by the wording in the book

[Chapter 6: Explicitely Defining Sparsely Populated Arrays And Conditions]

In chapter 6, on page 230, it is said that when you, intentionally, want to create a sparsely populated arrays it is best to be explicit about it in the following way:

 

var myList = [1, undefined, 3, undefined, 5];

 

However, this leads to a problem when using an if in condition in a for loop, like so:

 

for (var i = 0, count = myList.length; i < count; i++) {
if (i in myList) {
console.log(myList[i]);
}
}

 

Under normal circumstances, in a sparsely populated array, this would lead to only the defined elements (1, 3 and 5) outputting to the console. But when explicitely using undefined to create these "holes", it leads to the entire list, including undefined elements being outputted.

 

Full example:

 

var myList = [1, undefined, 3, undefined, 5];
for (var i = 0, count = myList.length; i < count; i++) {
if (i in myList) {
console.log(myList[i]);
}
}
1
undefined
3
undefined
5

 

This, however, does work:

 

var myList = [1, , 3, , 5];
for (var i = 0, count = myList.length; i < count; i++) {
if (i in myList) {
console.log(myList[i]);
}
}
1
3
5

[Chapter 5 Pursue: Check For One @ In Email]

Thank you!

[Chapter 5 Pursue: Check For One @ In Email]

I've been racking my brain over how to achieve this, but I'm stumped.

 

Here's the code I use in the relevant contact.js:

 

function process() {
'use strict';
//set initial check for validation to true because there are no errors yet
var okay = true;
//reference to email and comments elements
var email = document.getElementById('email');
var comments = document.getElementById('comments');
//validate email
if (!email || !email.value || (email.value.length < 6) || (email.value.indexOf('@') == -1)) {
 okay = false;
 alert('Please enter a valid email address');
}//end if
//validate comments
if (!comments || !comments.value || (comments.value.indexOf('<') != -1)) {
 okay = false;
 alert('Please enter your comments, without any HTML!');
}//end if
return okay;
}//end process() function
//event listener
function init() {
'use strict';
//call process upon submission of form
document.getElementById('theForm').onsubmit = process;
}//end init function()
window.onload = init;