This is definitely not the case for at least French and Russian, which means markup renderers now have to guess text language or force authors to declare such in some metadata header. And it gets even more complicated with inclusion of block quotes in different languages.
There should be one-- and preferably only one --obvious way to do it.
Although that way may not be obvious at first unless you're Dutch.
[...]
Namespaces are one honking great idea -- let's do more of those!I created a convention for defining sub-notes (with frontmatter) in a Markdown note and have found it really helpful over the past few years.
> Unicode has U+200B ZERO WIDTH SPACE for that purpose.
ZWSP is not at all “for that purpose”. If you mean this:
A—​
B
And if you’re willing to do preprocessing, you can just merge the lines, that’d actually work.
> In HTML and hence Markdown you can also use `<wbr>`.
I fail to see how <wbr> is relevant.
More generally, I see markup languages and the details of how they are rendered as largely orthogonal. You don’t necessarily need to invent a different markup language in order to adjust the rendering.
Instead of using an unbreakable em dash to rigidly and unbreakably connect two phrases by their last and first words, I prefer using an en dash, followed by a shy hyphen, and then another en dash, to elegantly hyphenate words connected by em dashes when they don't fit on the line. ;)
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