A tiny library that fixes whitespace in JavaScript template strings.
const items = [1, 2, 3]
const generateSitePage = (head, content) => fixWhitespace`
<!DOCTYPE html>
<html>
<head>
(Begin head..)${head}(..End head)
<meta charset='utf-8'>
</head>
<body>
<div id='content'>
${"Early insert!"} (Begin content x1..)${content}(..end content; begin content x2..)${content}(..end content!)
${"And back down."}
</div>
</body>
</html>
`
console.log(generateSitePage(
fixWhitespace`
<title>Hello, world!</title>
`,
fixWhitespace`
<ul>${items.map(x => `<li>${x}</li>`).join('\n')}</ul>
`
))<!DOCTYPE html>
<html>
<head>
(Begin head..)<title>Hello, world!</title>(..End head)
<meta charset='utf-8'>
</head>
<body>
<div id='content'>
Early insert! (Begin content x1..)<ul>
<li>1</li>
<li>2</li>
<li>3</li>
</ul>
<!-- Further indent at end! -->(..end content; begin content x2..)<ul>
<li>1</li>
<li>2</li>
<li>3</li>
</ul>
<!-- Further indent at end! -->(..end content!)
And back down.
</div>
</body>
</html>