React Question

index.jsx

<div className={(condition) ? 'grid-item Rejection Rejection--width2' : 'grid-item Rejection'}>
// How can I do this without repeating the grid-item and Rejection classes?
// Something like:
//<div className={"grid-item Rejection" if (condition) { "Rejection--width2" }}>

<div className={'grid-item Rejection ' + (condition) ? 'Rejection--width2' : ''}>

Using classnames:

var classNames = require('classnames')

<div className={classNames('grid-item Rejection', condition && 'Rejection--width2')}>

+1 for the classnames library. It may seem like a lot to solve just one problem but once you get used to it you'll use it all over the place. It completely eliminates the need for dirty string concatenation.

@insin, it's more idiomatic to use an object to hold conditions:

<div className={classNames('grid-item Rejection', { 'Rejection--width2' : condition })}>