Set up MarkdownCodeBlockFormatter

[angelikatyborska]

I wrote an Elixir formatter plugin that is able to format Elixir code in Markdown files. @jiegillet @neenjaw what do you think?

(I'll publish it to hex before merging)

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Automated comment created by PR Commenter 🤖.

[angelikatyborska]

Not a formatter feature 😛

[angelikatyborska]

Where desired, formatting can be turned off. For example here we want to show off a non-standard way to format this code to prove a point.

[neenjaw]

Nice, this looks pretty good!

My only thought is I don't know what is standard in the markdown standard for those formatter directives to ignore some blocks. But it works for me!

[angelikatyborska]

Part of the problem is that there is no one Markdown standard 😞 This syntax:

[]: # (elixir-formatter-disable-next-block)

It's an abused reference-style link. More generically, it's:

[reference-name]: https://example.com (Some link title)

Now, I don't know if all Markdown implementations support reference-style links, but Exercism definitely depends on them. I'm pretty sure that # must be a valid link href, and elixir-formatter-disable-next-block is a valid link title. The only thing I'm unsure about is an empty reference name. I didn't see any problems so far. It could also be non-empty (could be anything), but configlet generate moves all non-empty link references to the bottom of the markdown file which messes up with my intended use 😁

[jiegillet]

Outstanding! I love formatters :)

I left a couple of questions.

[jiegillet]

Why did this comment go at the bottom?

[angelikatyborska]

I moved it manually because the "reverse" part is not part of this code. The code only shows list creation, and then it's implied that you need to reverse later. Hence the comment should be last.

[jiegillet]

There is a specific point about what this evaluate to just below, maybe those shouldn't be formatted?

[angelikatyborska]

Well spotted