3 ms·

> GUI libraries are an interesting special case: They involve huge class hierarchies, lots of implementation inheritance, circular references, and tricky owners

> GUI libraries are an interesting special case: They involve huge class hierarchies, lots of implementation inheritance, circular references, and tricky ownership. I doubt they have to be. There are other ways to do GUI, see for instance how Light Table uses a database-like Entity Component System. https://www.youtube.com/watch?v=V1Eu9vZaDYw https://www.youtube.com/watch?v=V1Eu9vZaDYw

jerf 10y ago
I am fairly confident "someone" could write a composition-based UI. I know of no fundamental reason why that would be impossible, or even any more difficult than doing one with inheritance. However, that does not solve the problem that all the mature existing UI widget toolkits are based on inheritance, and that causes a serious "impedance mismatch" with languages that don't have inheritance. As I expect more languages to start privileging composition over inheritance, I also therefore expect this problem to continue to become more acute until "someone" finally solves it. However, GUI toolkits are huge and "someone" is likely to be a substantially-sized organization. The problem is going to have to become very painful before it is solved well.
- loup-vaillant 10y ago
  Granted, current GUI toolkits are huge. On the other hand, I have worked with Qt, and this convinced me most of the complexity there was a blend of avoidable bloat and a long tail of features few people ever use (a bit like offices suites). I'm pretty sure properly written GUI toolkits can be much smaller. As in, satisfying 90% of our needs in a couple thousand lines of code. (The remaining 10% might require heaps and heaps of code, but I'm sure it doesn't have to affect the core.) It's only an intuition at this point (I have yet to implement my own GUI toolkit). But I have reasons to believe this intuition is right: http://www.vpri.org/pdf/tr2012001_steps.pdf http://www.vpri.org/pdf/tr2012001_steps.pdf
  - jerf 10y ago
    Well, I guess I ought to put this in here, rather than rewrite it :) : https://news.ycombinator.com/item?id=12410471 https://news.ycombinator.com/item?id=12410471 The "long tail" is like the long tail of Excel or Word; yeah, everybody only uses 5% of it but everybody uses a different 5%.
  - shadowmint 10y ago
    I'm pretty sure properly written GUI toolkits can be much smaller... Given that as far as I know, there are no examples of tiny fully-featured GUI libraries (it's all either trivial like cgui or a massive bloated mammoth like qt/wpf/android), isn't that a bit of a rich statement? Like, I'm sure you can write a procedural generator in a handful of lines of code that spits out the full works of Shakespeare. It's probably possible, if you have the right seed and the right algorithm. ...but practically speaking, how do you actually build one? The same goes for UI libraries; certainly it should be possible (in theory) to have a minimal beautiful GUI libraries with an excellent API; but every attempt to build one seems to have failed. Perhaps the problem domain is actually more difficult than you're giving it credit for...
    - elcritch 10y ago
      It's certainly a tricky endeavor, but not impossible: - http://www.fltk.org/index.php http://www.fltk.org/index.php - https://github.com/froggey/Mezzano https://github.com/froggey/Mezzano Then again most gui libraries end up including networking, file handling, etc...
    - loup-vaillant 10y ago
      vpri.org managed to squeeze a GUI toolkit and a document format and the whole compiler toolchain required for the language (including rasterization) in about 20K lines of code, and it's fast enough to run in a laptop. I'm pretty sure we haven't explored the sheer depth of simplifications that can still be done.
      - shadowmint 10y ago
        Sounds cool. Got a link? I can't find anything on their website that seems to be that sort of thing?
        renox 10y ago
        I doubt that you'll find much.. They didn't release the code of their "crown jevel" (Frank, the 'word processor'), which makes me quite unimpressed about these year of research where the main result is a bunch of papers and demos but (nearly no) code (except for the OMeta part).
- carry_bit 10y ago
  You might be able to create something like React. The API would be composition-based, and the library would bottom out against an existing UI toolkit.

jerf 10y ago

I am fairly confident "someone" could write a composition-based UI. I know of no fundamental reason why that would be impossible, or even any more difficult than doing one with inheritance. However, that does not solve the problem that all the mature existing UI widget toolkits are based on inheritance, and that causes a serious "impedance mismatch" with languages that don't have inheritance. As I expect more languages to start privileging composition over inheritance, I also therefore expect this problem to continue to become more acute until "someone" finally solves it. However, GUI toolkits are huge and "someone" is likely to be a substantially-sized organization. The problem is going to have to become very painful before it is solved well.

loup-vaillant 10y ago
Granted, current GUI toolkits are huge. On the other hand, I have worked with Qt, and this convinced me most of the complexity there was a blend of avoidable bloat and a long tail of features few people ever use (a bit like offices suites). I'm pretty sure properly written GUI toolkits can be much smaller. As in, satisfying 90% of our needs in a couple thousand lines of code. (The remaining 10% might require heaps and heaps of code, but I'm sure it doesn't have to affect the core.) It's only an intuition at this point (I have yet to implement my own GUI toolkit). But I have reasons to believe this intuition is right: http://www.vpri.org/pdf/tr2012001_steps.pdf http://www.vpri.org/pdf/tr2012001_steps.pdf
- jerf 10y ago
  Well, I guess I ought to put this in here, rather than rewrite it :) : https://news.ycombinator.com/item?id=12410471 https://news.ycombinator.com/item?id=12410471 The "long tail" is like the long tail of Excel or Word; yeah, everybody only uses 5% of it but everybody uses a different 5%.
- shadowmint 10y ago
  I'm pretty sure properly written GUI toolkits can be much smaller... Given that as far as I know, there are no examples of tiny fully-featured GUI libraries (it's all either trivial like cgui or a massive bloated mammoth like qt/wpf/android), isn't that a bit of a rich statement? Like, I'm sure you can write a procedural generator in a handful of lines of code that spits out the full works of Shakespeare. It's probably possible, if you have the right seed and the right algorithm. ...but practically speaking, how do you actually build one? The same goes for UI libraries; certainly it should be possible (in theory) to have a minimal beautiful GUI libraries with an excellent API; but every attempt to build one seems to have failed. Perhaps the problem domain is actually more difficult than you're giving it credit for...
  - elcritch 10y ago
    It's certainly a tricky endeavor, but not impossible: - http://www.fltk.org/index.php http://www.fltk.org/index.php - https://github.com/froggey/Mezzano https://github.com/froggey/Mezzano Then again most gui libraries end up including networking, file handling, etc...
  - loup-vaillant 10y ago
    vpri.org managed to squeeze a GUI toolkit and a document format and the whole compiler toolchain required for the language (including rasterization) in about 20K lines of code, and it's fast enough to run in a laptop. I'm pretty sure we haven't explored the sheer depth of simplifications that can still be done.
    - shadowmint 10y ago
      Sounds cool. Got a link? I can't find anything on their website that seems to be that sort of thing?
      - renox 10y ago
        I doubt that you'll find much.. They didn't release the code of their "crown jevel" (Frank, the 'word processor'), which makes me quite unimpressed about these year of research where the main result is a bunch of papers and demos but (nearly no) code (except for the OMeta part).
carry_bit 10y ago
You might be able to create something like React. The API would be composition-based, and the library would bottom out against an existing UI toolkit.