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                <div data-component="helloWorld"></div>


                .validation-error {
  color: crimson;


                const helloWorld = {
  model: {
    message: "",
    response: "",
    validation: "",
    isSending: false
  actions(model) {
    return {
      setMessage(message) {
        model.message = message;
      sendMessage(message) {
        if (message === "") {
          model.validation = "Please enter a message.";
        } else {
          model.validation = "";
        // if your action returns a promise, comp will
        // ensure that render is called when it resolves
        return new Promise((resolve, reject) => {
          model.isSending = true;
          model.response = "";
          setTimeout(() => {
            model.response = `Your message was: ${message}`;
            // remember to resolve the promise, passing in
            // the updated model so it can be rendered
            model.isSending = false;
          }, 1000);
        .catch(err => {
  view() {
    return {
      render(model, html) {
        return html`
            <input type="text" data-keyup="setMessage(this.value)" placeholder="Type some words"/>
            <button data-click="sendMessage(this.dataset.message)" data-message="${model.message}">
                  ? "Sending..."
                  : "Send (1000ms delay)"}
            ${model.validation !== ""
              ? `<p class="validation-error">${model.validation}</p>`
              : `<h3>${model.response}</h3>`}

comp.create("helloWorld", helloWorld.actions, helloWorld.view, helloWorld.model)