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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM A Simple Example

Posted by Szabolcs Hetei-Bako
Szabolcs Hetei-Bako
6,559 Points

I get this error in the console:

After typing in everything correctly I get this message.

[Error] SyntaxError: Can't create duplicate variable that shadows a global property: 'myHeading'
Ben Schroeder
Ben Schroeder
22,818 Points
Ben Schroeder
Ben Schroeder
22,818 Points

Can you please copy and paste your script?

4 Answers

Nathan Gallagher
Nathan Gallagher
21,518 Points
Nathan Gallagher
Nathan Gallagher
21,518 Points

This is apparently a problem Safari has with declaring a let/const variable that shares the same name as a selected id attribute. I had some variables declared with const as you did and got the same error. Changed to let and still got it. Changed to var and it worked.

Szabolcs Hetei-Bako
Szabolcs Hetei-Bako
6,559 Points

Thanks Nathan :)

edinjusupovic
edinjusupovic
5,664 Points

Thanks Nathan. I was experiencing the same issue on Safari. Anyone know why its not working even with let? strange error.

Szabolcs Hetei-Bako
Szabolcs Hetei-Bako
6,559 Points
Szabolcs Hetei-Bako
Szabolcs Hetei-Bako
6,559 Points 
const myHeading = document.getElementById('myHeading');
const myButton = document.getElementById('myButton');
const myTextInput = document.getElementById('myTextInput');

myButton.addEventListener('click', () => {
 myHeading.style.color = 'red';

});
Szabolcs Hetei-Bako
Szabolcs Hetei-Bako
6,559 Points
Szabolcs Hetei-Bako
Szabolcs Hetei-Bako
6,559 Points

I have this problem in Safari. With Chrome it is working.

Jeremy Hamilton
Jeremy Hamilton
7,229 Points
Jeremy Hamilton
Jeremy Hamilton
7,229 Points

I has to do with how the window element has attributes for each HTML ID. It's known, but faster just to change to var or change the name of the constant.