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

Is message += and message =+ the same?

following...

1 Answer

Steven Parker
Steven Parker
230,024 Points

Those operations are quite different! The "+=" is the addition assignment operator. It adds the value from the variable on the left to the value on the right, and then puts the result back into the variable on the left. If used with strings, instead of adding values numerically, it joins them by concatenation.

On the other hand, "=+" is two operators, and is the same as "= +". So it's the normal assignment operator, with a "+" prepended to the expression on the right. The "+" part will have no effect on numbers, but it will convert a string into a number.