HTML Syntax: Threat or Menace?

Some developers love HTML: its syntax, its angle brackets, its duplicated tag names, its scent, its silky smooth skin. If you are among them, you probably don’t won’t like this post.

I appreciate the practicality of HTML: HTML is ubiquitous, so nearly every developer already knows it. Nearly every editor and IDE already syntax-highlights and auto-formats HTML. But I don’t care for HTML’s syntax. On some projects, I use tools that offer an alternative, simpler syntax for the underlying HTML/DOM data model.

Indentation-Based HTML Alternatives

The most popular HTML alternative syntax is a Python-like indentation-based syntax, in which element nesting in determined by start-of-line white space. Implementations of this idea include Jade, HAML, and Slim.

Of those, Jade seems the most polished, and there are multiple Jade implementations available: the original (JavaScript, for use in Node or the browser), Java, Scala, Python, PHP, and possibly others. Jade looks like this:

There is a free, helpful HTML to Jade converter online thanks to Aaron Powell, shown in the above image. It can be used to translate HTML documents or snippets to Jade in a couple of clicks.

Non-HTML HTML Advantages

1. Jade (and other tools) trivially do lot of things right, like balanced tags, with no need for IDE support.
2. Generated HTML will automatically be “pretty” and consistent
3. Generated HTML will always be well formed: Jade doesn’t have a way to express unbalanced tags!
4. Very concise and tidy syntax.
5. Cleaner diffs for code changes – less noise in the file means less noise in the diff.

Non-HTML HTML Disadvantages

1. Another Language to Learn: People already know HTML; any of these tools is a new thing to learn.
2. Build Step: any of these tools needs a build step to get from the higher level language to browser-ready HTML.
3. Limited development tool support – you might get syntax highlighting and auto-completion, but you will need to look around and set it up.

Non-Arguments

1. There is no “lock in” risk – any project using (for example) Jade as an alternative HTML syntax, could be converted to plain HTML templates in a few hours or less.
2. Since it is all HTML at runtime, there is no performance difference.

Conclusion

On balance, I think it is a minor win (nice, but not indispensable) to use a non-HTML HTML syntax. At work, we do so on many of our projects..