• https://developer.mozilla.org/ja/docs/Web/JavaScript/Reference/template_strings

const a = 'world';
const s = `Hello ${a}!`;
console.log(s)                // => Hello world!と出力

function uc(strings, ...values) {
  return String.raw({raw: strings}, ...values.map(v => v.toUpperCase()));
}

const a = 'world';
const s = uc`Hello ${a}!`;
console.log(s);               // => Hello WORLD!と出力

テンプレートリテラルを使わずに、同様の処理を実装できる。

const a = "Sun";
const b = "platet";

`the ${a} is not a ${b}.` ===  String.raw({raw:[ "the ", " is not a ", "."]}, a, b);