function useCounter ( ) { const count = $signal ( 0 ) ; effect : { console . log ( 'Current count:' , count ) ; } return $refSignal ( count ) ; } export default function App ( ) { let count = $derefSignal ( useCounter ( ) ) ; const message = $memo ( `Count: ${ count }` ) ; effect : { console . log ( message ) ; } function increment ( ) { count += 1 ; } return ( < > < button type = "button" onClick = { increment } > { message } < /button> < $show when = { count % 2 === 0 } fallback = { < h1 > Odd < /h1>}> < h1 > Even < /h1> < /$show> < />); }