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 React Basics (2018) Understanding State Understanding State Review

Posted by Charlie Prator
.a{fill-rule:evenodd;}techdegree seal-36
Charlie Prator
Front End Web Development Techdegree Graduate 19,854 Points

What does the exclamation point in this code stating?

confirmGuest = () => {
  this.setState( prevState => ({ 
    isConfirmed: !_________.isConfirmed
  }));
}

Is the above saying to update the state of isConfirmed through the negation of its previous state? So, if the previous state of isConfirmed is false, then we're changing it to true with the exclamation point, right?

1 Answer

Marie Franklin
Marie Franklin
13,367 Points

yes!... just toggling the value of isConfirmed

isConfirmed: !prevState.isConfirmed