Vue.jsでTypeScriptを利用する

vue create type-test

Vue CLI v4.1.1
? Please pick a preset: 
  default (babel, eslint) 
❯ Manually select features 

? Check the features needed for your project: 
 ◯ Babel
❯◉ TypeScript
 ◯ Progressive Web App (PWA) Support
 ◯ Router
 ◯ Vuex
 ◯ CSS Pre-processors
 ◯ Linter / Formatter
 ◯ Unit Testing
 ◯ E2E Testing

? Use class-style component syntax? Yes
? Use Babel alongside TypeScript (required for modern mode, auto-detected polyfills, transpiling JSX)? No
? Where do you prefer placing config for Babel, ESLint, etc.? In package.json
? Save this as a preset for future projects? No

cd type-test
npm run serve

<template>
  <div class="hello">
    <h1>{{ msg }}</h1>
    <h1>{{ text }}</h1>
  </div>
</template>

<script lang="ts">
import { Component, Prop, Vue } from 'vue-property-decorator';

@Component
export default class HelloWorld extends Vue {
  @Prop() private msg!: string;
  text: string = "Hello Text";

  get textLower(): string {
    return this.text.toLowerCase();
  }
}
</script>

<!-- Add "scoped" attribute to limit CSS to this component only -->
<style scoped>
h3 {
  margin: 40px 0 0;
}
ul {
  list-style-type: none;
  padding: 0;
}
li {
  display: inline-block;
  margin: 0 10px;
}
a {
  color: #42b983;
}
</style>