About the compatibility story... [LWN.net]

About the compatibility story...

Posted Sep 17, 2025 20:51 UTC (Wed) by warrax (subscriber, #103205)
In reply to: To become success story by spacefrogg
Parent article: Typst: a possible LaTeX replacement

Yes, TeX itself has been rock stable, of course, but the idea that you could just rebuild LaTeX documents years after making them hasn't been true for me. I can't remember the exact packages I used which broke, but I'm certain it wasn't anything particularly advanced. Of course it broke with inscrutable error messages, etc.

I do think you're correct that backward[1] compatibility *is* important, but the LaTeX ecosystem as a whole isn't necessarily great at that... it very much depends on what packages you use.

[1] Future versions being able to process old code/documents is usually referred to as 'backward' compatibility.

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About the compatibility story...

Posted Sep 17, 2025 21:24 UTC (Wed) by dskoll (subscriber, #1630) [Link] (4 responses)

Hmm... I have three manuals I started writing 20 years ago and continued writing through 2018; they total almost 600 pages and still build perfectly fine on whatever version of LaTeX ships with Debian 13.

I don't go crazy with untested or new packages, though... all of the packages I use have been around for a long time and are very stable.

About the compatibility story...

Posted Sep 18, 2025 2:18 UTC (Thu) by Cyberax (✭ supporter ✭, #52523) [Link] (3 responses)

I have LaTeX files from university days (early 2000-s). I can't render them anymore. Ironically, MS Word documents that I wrote during that time are perfectly readable.

About the compatibility story...

Posted Sep 18, 2025 9:38 UTC (Thu) by paulj (subscriber, #341) [Link] (1 responses)

Whether the MS Word documents render the same as they did before, hell whether they render the same on one PC as another, is another question though. (And the answer is "often not"). So your "perfectly" very likely has a wide margin of error.

About the compatibility story...

Posted Sep 18, 2025 13:02 UTC (Thu) by pizza (subscriber, #46) [Link]

> Whether the MS Word documents render the same as they did before, hell whether they render the same on one PC as another, is another question though.

...Even on the *same* PC, with the *same* version of Word, "rendering the same" was not guaranteed.

(Back in the day, I recall that merely changing the printer driver was sufficient to cause the document to paginate differently..)

About the compatibility story...

Posted Sep 18, 2025 17:12 UTC (Thu) by hholzgra (subscriber, #11737) [Link]

My early 90s experience was different, I wrote my bachelors thesis with WinWord 2.0a originally, then after switching universities for my masters degree they made it clear that they would expect me to use LaTeX, so as a learning exercise I re-did the complete thesis using LaTeX (somewhere around the switch from 2.09 to 2ε).

WinWord could already no longer process it properly when WinWord 6.0; the version right after 2.0a, came out.

The LaTeX version worked all the way until late 1999, when due to a series of mishaps the source was lost and I was left with only the PDF result, which I still have. (Generating PDF from Word documents on the other hand was basically unheard of back in the 1990s ...)

I also still have a few smaller texts I've written after the 1999 backup disaster, and these I can still process using current LaTeX versions.

About the compatibility story...

Posted Sep 17, 2025 21:26 UTC (Wed) by iabervon (subscriber, #722) [Link] (2 responses)

I think there was originally a model of fetching the packages you were using and storing them with the document that used them (and not continuing to update those copies); you had to go and get packages and get them again for them to change. As networking got faster, we switched to effectively having a local mirror of CTAN that you used packages from directly and updated periodically, which means that maintainers who aren't thinking about long-term backwards compatibility break old documents.

About the compatibility story...

Posted Sep 18, 2025 20:54 UTC (Thu) by SLi (subscriber, #53131) [Link]

Have you tried modifying those .sty files?

If only the underlying language was something modern and somehow modular and encapsulated instead of a weird macro mess with not-really-scopes.

Maybe I never got deep enough into it to really appreciate its cleverness (now I do appreciate that it's 50 years old), but in my experience it doesn't exactly take just "not thinking" to not break something by an unrelated change.

About the compatibility story...

Posted Sep 18, 2025 20:58 UTC (Thu) by ejr (subscriber, #51652) [Link]

This. Unfortunately some functionality relies on external programs (e.g. eps<->X conversions). Those do bitrot.

There was ConTeXt as well. I'm not sure of its status. And "worse is better" seems to have been a thing for me this week in many venues.

About the compatibility story...

Posted Sep 18, 2025 20:49 UTC (Thu) by SLi (subscriber, #53131) [Link]

I use LaTeX because the other options tend to suck more, but I sure hope something more solid replaces it. As of now, I understand TeX enough to wonder if it really seemed a good idea even when it was invented; but, granted, the TeX part is relatively solid, in the same way perhaps as MS-DOS is relatively solid and it's all the applications causing all the problems.

I think one big problem that I've seen in my field of CS is that people have become used to the output of LaTeX to the extent that everything else looks "unprofessional" to them merely by virtue of being different, even if it fixes some real annoyance in LaTeX output.

So while I still do my maths and typesetting often in LaTeX, I'm actually happy that the modern practitioners are refusing to take that route, even if it means them using Word. We shouldn't teach people to rely on stuff built on MS-DOS and Cobol either, even if the best typesetting tool remains some obscure DOS executable.