firstBook = linkedSignal(() => this.books()[0]);

src/app/books/book-list.component.ts

@@ -15,6 +15,9 @@ export class BookListComponent {
     computation: books => books[0]
   });
 
+  // this also works (shorthand version)
+  // firstBook = linkedSignal(() => this.books()[0]);
+
   overrideFirstBook() {
     // Manually updating `firstBook`, which now returns 'jQuery'
     this.firstBook.set('jQuery');

src/app/books/book/book.component.ts

@@ -20,7 +20,6 @@ export class BookComponent {
   // this also works:
   // rating = linkedSignal(() => this.book().rating);
 
-
   doRateUp() {
     const newRating = this.rating() + 1;
     this.rating.set(newRating);