Jonathan Ionath
ionathan.ch · Personal blog · on HN since 2022
Jonathan Ionath writes about typography, Unicode and LaTeX, including a research trail into the mysterious character U+237C.
What HN saysCommenters link it for the investigation into the origin and meaning of U+237C, and point to his CV page.
20HN people shared it
10linked it in comments
11stories submitted
709story points
7 months agolast shared
2022people per year2026
Most-shared posts
- 1U+237C ⍼ Right Angle with Downwards Zigzag Arrow11 people · 667 points · first shared 2022 · 295 comments on HN
- 2Cv2 people · first shared 2023
- 3U+237C ⍼ Is Azimuth1 people · 18 points · first shared 2026 · 3 comments on HN
- 4Update: U+237C ⍼ &Angzarr;1 people · 11 points · first shared 2023 · discussion on HN
- 5U+237C ⍼ Is (Also) S9576 ⍼1 people · 8 points · first shared 2024 · discussion on HN
- 6Little LaTeX Pearls1 people · 3 points · first shared 2026 · discussion on HN
- 7What's in a GIF?1 people · 2 points · first shared 2024 · discussion on HN
- 8Sized types1 people · first shared 2023
- 9Angzarr.html;1 people · first shared 2022
- 10Berthold%201900.jpg1 people · first shared 2026
What HN people wrote when they linked it
nickcw · 2022-04-13
Seems like a nice follow on from https://ionathan.ch/2022/04/09/angzarr.html which was discussed here https://news.ycombinator.com/item?id=31012865
cookiengineer · 2026-03-11
Check the photos in the article, specifically this one [1]
"Haussystem Didot", the title of the catalog, refers to a letter setting by the printing agency Didot, which is the one I linked on wikipedia.
The Gallica scans are linked in the wikipedia article. Each of those chapters has hundreds of pages.
I highly doubt that you eye scanned thousands of pages in French handwritten and mixed typesetted ... within less than a day. You definitely must be lying, they take months to read.
[1] https://ionathan.ch/assets/images/angzarr/Berthold%201900.jpg
voxadam · 2023-07-24
How do you decide which characters to index? The current Unicode release (15.0) includes 149,186 individual characters. I suppose you can probably ignore U+237C (Right Angle with Downwards Zigzag Arrow) seeing as nobody seems to know what it denotes.[0][1]
[0] https://news.ycombinator.com/item?id=31012865
[1] https://ionathan.ch/2022/04/09/angzarr.html
omoikane · 2023-06-17
The "timeline" link in the article is broken (links to localhost:4000), correct link should be
https://ionathan.ch/2022/04/09/angzarr.html#summary-timeline
aleph_minus_one · 2023-06-17
> Cambridge alum here (for my BA in 2009) but I'm in CA now. Would be willing to try putting in the request. Not sure how to contact Jonathan Chan...
Look at https://ionathan.ch/cv.html
HappyPanacea · 2023-06-06
This is also not my area of expertise, but considering they are using sized types to prove termination through well-foundness so they are probably suppose to be ordinals where we can have ω < ω+1 but for some reasons they decide to forgo to distinguish between everything larger than ω and denote it as inf.
Edit: I found an explanation https://ionathan.ch/2021/08/04/sized-types.html
zinekeller · 2022-07-14
And this... character with an unknown meaning or purpose: U+237C ⍼ RIGHT ANGLE WITH DOWNWARDS ZIGZAG ARROW (https://ionathan.ch/2022/04/09/angzarr.html; https://news.ycombinator.com/item?id=31012865)
olivierestsage · 2022-07-14
Reminds me of the case of U+237C ⍼ RIGHT ANGLE WITH DOWNWARDS ZIGZAG ARROW [0], also discussed on HN [1].
[0] https://ionathan.ch/2022/04/09/angzarr.html
[1] https://news.ycombinator.com/item?id=31012865
fabbari · 2022-05-06
Link to the actual article: https://ionathan.ch/2022/04/09/angzarr.html
formerly_proven · 2023-06-17
An email address is here: https://ionathan.ch/cv.html