Support for semantic tokens - date, person, toc, label...

[osfprieto]

As part of my work, we're trying to produce richer content on our flows. Our different layers communicate using GFM but we've had to use custom tags to communicate the semantics of some instances: Dates, Tables of contents, Mentions, Labels...

Most of these are generic enough that they can easily be considered to be supoprted within the markdown spec, especially to help produce richer content across apps.

So far we've started using custom html tags but it'd be great to have some common definition instead of relying on

Date

m-date tag with a string that can be parsed by the Date JS constructor

<m-date>YY-MM-DD</m-date>

Table of contents

m-toc tag that allows the parser to handle however it may see fit to render a table of contents.

<m-toc></m-toc>

[osfprieto]

Well, m-date can be represented quite similarly by the time tag so let's disregard that.

I'd be mostly inclined to discuss the toc representation.

[taufik-nurrohman]

If I were you, I would consider using the autolink syntax with a custom protocol to make it appear like a custom element. This syntax doesn’t have a list of valid protocols, so you can pretty much use any protocol as long as it uses at least 2 letters:

<custom:toc>

Then perform post-processing on the generated link element:

let tableOfContents = document.querySelectorAll('p>a[href^="custom:toc"]:only-child');
tableOfContents.forEach(tableOfContent => {
    replaceWithTableOfContentMarkup(tableOfContent.parentNode);
});

[taufik-nurrohman]

Other ideas:

<user:user-name>

<youtube:youtube-id>

<embed:embed-id?embed-param-1=true&embed-param-2=123>