Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript JavaScript Basics Working with Strings Combine and Manipulate Strings

Cannot read property '1' of null

I don't know what is what I'm doing wrong

app.js
let firstName;
let lastName;
let role = 'developer';

firstName = "Enrique";
lastName = "Gimenez Vera";

let msg= firstName + ' ' + lastName ',' + role ;

2 Answers

Steven Parker
Steven Parker
231,269 Points

I don't quite understand that message, but there is a concatenation operator ("+") missing between "lastName" and the string following it.

Once of you fix that, the challenge will remind you that you need a different separator (": " instead of ",").

You are missing a + after lastName here:

let msg= firstName + ' ' + lastName ',' + role ;

In addition to this check your final string to see if it matches the format in the instructions

Thank you!