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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Child Traversal

Posted by ammarkhan
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ammarkhan
Front End Web Development Techdegree Student 21,661 Points

Challenge working but not passing

My code is as follow 

const section = document.querySelector('section');
let paragraphs = section.children;

for( i = 0; i < paragraphs.length; i++ ){
    paragraphs[i].style.color = "blue"; 
}

I don't see anything wrong it the code as I tried on tried on Jsbin https://jsbin.com/gokanudefa/edit?html,js,output but It is not passing here!

app.js 
const section = document.querySelector('section');
let paragraphs = section.children;

for( i = 0; i < paragraphs.length; i++ ){
    paragraphs[i].style.color = "blue"; 
}
index.html 
<!DOCTYPE html>
<html>
    <head>
        <title>Child Traversal</title>
    </head>
    <body>
        <section>
            <p>This is the first paragraph</p>
            <p>This is a slightly longer, second paragraph</p>
            <p>Shorter, last paragraph</p>
        </section>
        <footer>
            <p>&copy; 2016</p> 
        </footer>
        <script src="app.js"></script>
    </body>
</html>

2 Answers

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there! You're doing great, and your code would be fine except that challenges use the "use strict";. Among other things, this means that a global variable may not be implicitly declared. That might not make much sense right now, but your i variable is not being declared with a let or a var. This means that the variable will default to global, which is not allowed by strict mode.

In the setup of your for loop it will need either for(var i = 0 ... or for(let i = 0....

Hope this helps! :sparkles:

Stuart Wright
Stuart Wright
41,120 Points
Stuart Wright
Stuart Wright
41,120 Points

The issue is that you haven't declared i in the for loop:

for(i=0; i < paragraphs.length; i++ )

You need to add either var or let before your i=0.

As shown by your jsbin example, your code does work correctly for this small example, but can lead to issues once you're working with larger projects - explanation here:

https://stackoverflow.com/questions/6881415/when-is-the-var-need-in-js

Edit: I see that Jennifer beat me to it, but I'll leave my answer here because I think the Stack Overflow answer is worth a read. :)