Linux

considers tradeoffs

So, if it were me, I'd probably use a text editor, as the big text editors are going to be able to do the rest of those. I've authored text in a number of lightly-annotated-text formats like Markdown and similar (AsciiDoc, Docbook, Markdown), and I always did it in emacs, and generally vim has analogous functionality.

If you don't mind me asking, what is the use case for this? Markdown originally had the design goal to be easily-editable as plain text -- that is, one could view it as plain text almost as well as in a rendered form. That was kind of its selling point relative to many other rich text markup languages; it was intended to let a user edit and read it in a plain-text editing environment, without even colorization and such.

Markdown, unlike, say, PDF or Microsoft Word or something, is intended to be display-device-agnostic. That is, if you distribute a Markdown file to others, what the end user will see may differ from what you see, because Markdown intentionally abstracts the specifics of how the material is displayed. Normally, WYSIWYG is mostly-useful for formats that don't do this. If you're using Markdown to author PDFs or printed pages or something and then using that format for distribution, I get that. But if you're handing out Markdown, what you see might not be what the end user sees; screen size differences, typeface differences, other things may pretty-dramatically change what they see. Even above-and-beyond device differences, the Lemmy Web UI, Mbin, the Lemmy clients that I've used, Reddit, and GitHub all use intentional variations on the basic Markdown format. IIRC from last time I used pandoc, it supports multiple of the different dialects, but even it can't provide a representation for every one. Lemmy recently ripped out the auto-renumbering of numbered lists. IIRC either Reddit or Lemmy disabled huge top-level headers after people abused them to flood threads (though maybe that's a per-community/subreddit CSS thing). Reddit doesn't support Markdown's syntax for inline images (well, old.reddit doesn't, at any rate, and I haven't tested new.reddit). Many websites and client software packages that present Markdown permit a user to view it in light-on-dark or dark-on-light or have other theming options.

Is it to make sure that there are no errors in the Markdown leading to some kind of wonky display, say (like a table row missing a trailing pipe or something)? There may be a non-editable-WYSIWYG way to accomplish that that might work with text editors. pandoc may have the ability to emit errors, and it looks like there are Markdown linting packages. It may be possible to rig those up to a text editor to highlight any errors. If I were doing it in emacs, I'd guess that flycheck can run a command in the background during idle time to check for errors and flag them. I don't know how vim does it, but I'm sure that it has an analogous feature.

kagis

It looks like flycheck already does support running markdownlint in the background to highlight errors in Markdown, actually:

https://www.flycheck.org/en/latest/languages.html

Supported Languages

Markdown

markdown-markdownlint-cli

Check Markdown with markdownlint-cli.

goes to try it out

On my system, I just needed to install markdownlint, and then enable the flycheck minor mode (M-x flycheck-mode) when in markdown-mode. Then emacs starts highlighting errors in the Markdown text, and one can get a list of errors in the document and jump to each.

It looks like markdownlint is pretty nitpicky out of the box (warns about line length, trailing whitespace, multiple consecutive blank lines), but I expect that that's configurable. It also did pick up on table column count mismatches, which is the main thing that I can think of to ask it for.

I also see a couple of vim extensions for markdownlint. Can't speak as to their functionality, but there's some level of integration there as well.