Support for markdown callouts

[Adamkadaban]

Are there any plans to support markdown callouts like these?

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They're supported on github, gitbook, obsidian, and probably more. This addition would make compatibility a bit easier.

I currently have a jekyll plugin for this but it's not very well made and requires liquid templates
https://github.com/Adamkadaban/jekyll-alerts-plugin

[gettalong]

As far as I can see the syntax is just plain Markdown but the interpretation from standard Markdown is different, i.e. the output is different.

If you want to have custom HTML output for this, you need to subclass the HTML converter and adapt the convert_blockquote method appropriately.

[benpickles]

Is this something that could live in kramdown-parser-gfm, maybe even enabled by default? It feels like perhaps not because it specifically says "parser" and not "converter" but...

[gettalong]

The GFM parser could also detect those lines and create different AST nodes to represent the callouts. Then the converter need not be changed. I just mentioned the converter because it is much each easier to adapt it to ones needs.

[benpickles]

I took your pointer and monkeypatched the converter, you can see it in action here https://parklife.dev/colophon (source: https://github.com/benpickles/parklife.dev/blob/main/lib/kramdown_enhancements.rb).

It was only once I'd implemented the change that I understood why it's not quite so simple to add support to Kramdown: because the ultimate output is entirely dependent on the wants of the developer. In my case I wanted to output an <aside> and a heading, and include icons and colours, whereas GitHub output a <div> and some <p>s (and icons and colours), others might want something completely different.

I haven't looked at the parser, I'm guessing it might be a better place to put things so that a specific alert callout converter method could be defined instead of overloading the convert_blockquote method. But I wouldn't know where to start... Any tips?!

BTW working within Kramdown for this really felt like the right place. I've previously either modified the Markdown before converting or the HTML after converting but working with Kramdown Elements felt a lot more healthy.

[gettalong]

In the parser you could define a new element type :callout and insert that instead of the blockquote into the AST. Then each converter would need to define a convert_callout method that converts the callout into the required format.