v-if, v-else-if and v-show in Vue
Vue interview exercise on Templates & reactivity, difficulty 1 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.
Write Loader with props `state` ("loading" | "error" | "ready"), `message` (string, default "") and `items` (string[], default []): <p class="loading">Loading…</p> while loading, <p class="error"> with the message on error, and when ready either <p class="empty">No items</p> or a <ul> of <li>s. Below that, a <button class="toggle"> that shows or hides (v-show, so it stays in the DOM) <p class="details">N items</p>, hidden at first.
Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.