This is pretty nice if you have an editor with block mode (like vim) and you are faster with a keyboard than a mouse (most programmers). It integrates well with text based version control and degrades gracefully in that users who don't have the tools and are just looking at the source can probably still read it, and even edit it.
It would be an improvement for the page that HN links to if the HTML snippet was surrounded by <body></body> so it worked out of the box.
Tips:
Don't use underscores for horisontal lines - use dashes (minus signs).
A vertical arrow that points at a text will collide with the text unless you add a blank line.
Rounded corners are nice. You get these by using . (period) or ' (single quote) instead of + (plus) to join lines. Use period to join to a vertical line below the horizontal line, and single quote to join to a vertical line above the horizontal line.
I tried using this for the control flow diagrams in V8's regexp implementation, which are documented with ASCII art in jsregexp.cc Results are here: https://twitter.com/erikcorry/status/1548954799290421249
This link explains it better than the page HN links to: https://code.sgo.to/2022/06/20/typographic-diagrams.html
It would be an improvement for the page that HN links to if the HTML snippet was surrounded by <body></body> so it worked out of the box.
Tips:
Don't use underscores for horisontal lines - use dashes (minus signs).
A vertical arrow that points at a text will collide with the text unless you add a blank line.
Rounded corners are nice. You get these by using . (period) or ' (single quote) instead of + (plus) to join lines. Use period to join to a vertical line below the horizontal line, and single quote to join to a vertical line above the horizontal line.