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Maybe it's time for me to switch to a text-only browser. When CSS becomes Turing-complete it seems that even NoScript won't help me from nefarious web pages.

robin_reala 5y ago
CSS is already Turing-complete if you set up an execution environment of some checkboxes and require user interaction to ‘advance the tape’: https://stackoverflow.com/a/5239256/453783 https://stackoverflow.com/a/5239256/453783
jhoelzel 5y ago
we have come full circle! you should now browse websites with the terminal just to be secure. but then you get blocked for not having the right headers....
- catfishx 5y ago
  I wonder if there are any vulnerabilities in terminals which could be exploited
  - deleted 5y ago
    [deleted]
charcircuit 5y ago
What does Turing completeness have to do with anything? Physical computers aren't even Turing complete themselves.
- colejohnson66 5y ago
  Under what definition is a physical computer not Turing Complete? The lack of infinite memory? That requirement would preclude literally everything but theoretical computers. It’s a lot more logical to talk in terms of “if there was infinite tape, would this thing Turing Complete?” Brainf** is famously Turing Complete and can be executed on any desktop you can think of. That alone is enough to prove that your desktop itself is Turing Complete.
  - ggrrhh_ta 5y ago
    I think that the parent comment is actually supporting your point. It does not need to be Turing Complete to be extremely useful. Conversely, a model of computation (CSS) could be Turing Complete (with infinite memory, etc.) and lack arbitrary access the host filesystem (e.g., it only allows to read specific read-only files), thus being useless.
  - carnitine 5y ago
    Turing completeness is a mathematical concept, why try and extend it to physical devices? Ever computer I can think of corresponds to a finite state machine.
  - charcircuit 5y ago
    Even if you let computers have infinite memory it still doesn't matter that much if a language is Turing complete. The person I replied to seemed to be more worried about CSS reading localstorage compared to being able to recognize a recursively enumerable language.
smoyer 5y ago
Or at a minimum, don't use Chrome ...
streamofdigits 5y ago
It may really be time to re-examine the text-only proposition (gemini style). There is this fear of missing out on visual content but I suspect this too could be handled.
colejohnson66 5y ago
It is Turing Complete.[0] And before anyone says otherwise, Turing Completeness does not preclude a “crank” used in that post. [0]: https://stackoverflow.com/a/5239256/1350209 https://stackoverflow.com/a/5239256/1350209
- carnitine 5y ago
  That’s definitely not Turing complete. Not because of the crank, but the fact the exact number of memory cells is hard coded. I can run an n-cell Rule 110 simulation on a DFA, which is obviously not Turing complete.
  - tshaddox 5y ago
    The exact number of memory cells in your computer is also bounded.
    - carnitine 5y ago
      Yes, but things we actually care and prove to be Turing complete are not. There’s no up front memory limitation in the lambda calculus or Javascript or Prolog.
      - tshaddox 5y ago
        But you can increase the “hard-coded” amount of memory in this CSS demo too.
        carnitine 5y ago
        To a finite amount, as part of the program itself. If I write a JS program that loops infinitely, pushing a number to an array, that will consume infinite memory by the standards of the JS spec. There’s no hard, upfront bound on memory. If we can hardcode memory limitations in our programs, then every ‘uncomputable’ problem just becomes a lookup table.
rosndo 5y ago
Turing completeness means literally nothing. It’s all about the APIs.
zekica 5y ago
CSS is already Turing-complete. https://lemire.me/blog/2011/03/08/breaking-news-htmlcss-is-turing-complete/ https://lemire.me/blog/2011/03/08/breaking-news-htmlcss-is-t...
catfishx 5y ago
But JS is still required to for this to work, the title is a bit misleading

robin_reala 5y ago

CSS is already Turing-complete if you set up an execution environment of some checkboxes and require user interaction to ‘advance the tape’: https://stackoverflow.com/a/5239256/453783 https://stackoverflow.com/a/5239256/453783

jhoelzel 5y ago

we have come full circle! you should now browse websites with the terminal just to be secure. but then you get blocked for not having the right headers....

catfishx 5y ago
I wonder if there are any vulnerabilities in terminals which could be exploited
- deleted 5y ago
  [deleted]

charcircuit 5y ago

What does Turing completeness have to do with anything? Physical computers aren't even Turing complete themselves.

colejohnson66 5y ago
Under what definition is a physical computer not Turing Complete? The lack of infinite memory? That requirement would preclude literally everything but theoretical computers. It’s a lot more logical to talk in terms of “if there was infinite tape, would this thing Turing Complete?” Brainf** is famously Turing Complete and can be executed on any desktop you can think of. That alone is enough to prove that your desktop itself is Turing Complete.
- ggrrhh_ta 5y ago
  I think that the parent comment is actually supporting your point. It does not need to be Turing Complete to be extremely useful. Conversely, a model of computation (CSS) could be Turing Complete (with infinite memory, etc.) and lack arbitrary access the host filesystem (e.g., it only allows to read specific read-only files), thus being useless.
- carnitine 5y ago
  Turing completeness is a mathematical concept, why try and extend it to physical devices? Ever computer I can think of corresponds to a finite state machine.
- charcircuit 5y ago
  Even if you let computers have infinite memory it still doesn't matter that much if a language is Turing complete. The person I replied to seemed to be more worried about CSS reading localstorage compared to being able to recognize a recursively enumerable language.

smoyer 5y ago

Or at a minimum, don't use Chrome ...

streamofdigits 5y ago

It may really be time to re-examine the text-only proposition (gemini style). There is this fear of missing out on visual content but I suspect this too could be handled.

colejohnson66 5y ago

It is Turing Complete.[0] And before anyone says otherwise, Turing Completeness does not preclude a “crank” used in that post. [0]: https://stackoverflow.com/a/5239256/1350209 https://stackoverflow.com/a/5239256/1350209

carnitine 5y ago
That’s definitely not Turing complete. Not because of the crank, but the fact the exact number of memory cells is hard coded. I can run an n-cell Rule 110 simulation on a DFA, which is obviously not Turing complete.
- tshaddox 5y ago
  The exact number of memory cells in your computer is also bounded.
  - carnitine 5y ago
    Yes, but things we actually care and prove to be Turing complete are not. There’s no up front memory limitation in the lambda calculus or Javascript or Prolog.
    - tshaddox 5y ago
      But you can increase the “hard-coded” amount of memory in this CSS demo too.
      - carnitine 5y ago
        To a finite amount, as part of the program itself. If I write a JS program that loops infinitely, pushing a number to an array, that will consume infinite memory by the standards of the JS spec. There’s no hard, upfront bound on memory. If we can hardcode memory limitations in our programs, then every ‘uncomputable’ problem just becomes a lookup table.

rosndo 5y ago

Turing completeness means literally nothing. It’s all about the APIs.

zekica 5y ago

CSS is already Turing-complete. https://lemire.me/blog/2011/03/08/breaking-news-htmlcss-is-turing-complete/ https://lemire.me/blog/2011/03/08/breaking-news-htmlcss-is-t...

catfishx 5y ago

But JS is still required to for this to work, the title is a bit misleading