From f17a3b0a8c4c6b98bdccc0092d744a070dfd337e Mon Sep 17 00:00:00 2001 From: EmacsConf Date: Sun, 3 Dec 2023 12:48:20 -0500 Subject: update cubing captions --- ...emacs--vasilij-wasamasa-schneidermann--main.vtt | 356 ++++++++++----------- 2023/info/cubing-after.md | 354 ++++++++++---------- 2023/info/cubing-before.md | 2 +- 3 files changed, 356 insertions(+), 356 deletions(-) (limited to '2023') diff --git a/2023/captions/emacsconf-2023-cubing--speedcubing-in-emacs--vasilij-wasamasa-schneidermann--main.vtt b/2023/captions/emacsconf-2023-cubing--speedcubing-in-emacs--vasilij-wasamasa-schneidermann--main.vtt index 2ae22295..db303c95 100644 --- a/2023/captions/emacsconf-2023-cubing--speedcubing-in-emacs--vasilij-wasamasa-schneidermann--main.vtt +++ b/2023/captions/emacsconf-2023-cubing--speedcubing-in-emacs--vasilij-wasamasa-schneidermann--main.vtt @@ -256,548 +256,548 @@ So at this point the organizer should hopefully show 00:03:54.200 --> 00:03:57.999 a small video I've prepared, a one minute video showing how -00:03:58.000 --> 00:04:03.080 +00:03:58.000 --> 00:05:15.239 I actually use this to solve a cube and to time my solve. NOTE Challenges: Representing the cube -00:05:19.840 --> 00:05:22.959 +00:05:15.240 --> 00:05:18.508 Okay, so building this thing, there were several challenges. -00:05:22.960 --> 00:05:24.959 +00:05:18.509 --> 00:05:20.508 The first one was how do I even represent -00:05:24.960 --> 00:05:26.919 +00:05:20.509 --> 00:05:22.468 the state of a Rubik's cube. -00:05:26.920 --> 00:05:29.959 +00:05:22.469 --> 00:05:25.508 For this there are many possible representations, -00:05:29.960 --> 00:05:32.159 +00:05:25.509 --> 00:05:27.708 no obvious best solution. -00:05:32.160 --> 00:05:34.079 +00:05:27.709 --> 00:05:29.628 I did not, well, what helped me was that -00:05:34.080 --> 00:05:36.439 +00:05:29.629 --> 00:05:31.988 I did not have to programmatically solve this thing, -00:05:36.440 --> 00:05:39.639 +00:05:31.989 --> 00:05:35.188 so I picked the easiest possible representation -00:05:39.640 --> 00:05:42.719 +00:05:35.189 --> 00:05:38.268 which is just an array of every single facelet. -00:05:42.720 --> 00:05:46.959 +00:05:38.269 --> 00:05:42.508 For a 3x3 cube you have 9 facelets on one side, -00:05:46.960 --> 00:05:51.719 +00:05:42.509 --> 00:05:47.268 so times 6 sides you would have 54 elements in this array. -00:05:51.720 --> 00:05:54.159 +00:05:47.269 --> 00:05:49.708 So with this representation, it's very simple, -00:05:54.160 --> 00:05:56.839 +00:05:49.709 --> 00:05:52.388 but it's kind of weird to do scrambles with this. -00:05:56.840 --> 00:05:59.359 +00:05:52.389 --> 00:05:54.908 But otherwise, it worked very, very well. -00:05:59.360 --> 00:06:01.719 +00:05:54.909 --> 00:05:57.268 In the future, I plan to learn some group theory, -00:06:01.720 --> 00:06:03.199 +00:05:57.269 --> 00:05:58.748 pick a better representation -00:06:03.200 --> 00:06:05.639 +00:05:58.749 --> 00:06:01.188 and do this in a much, much more elegant way -00:06:05.640 --> 00:06:12.319 +00:06:01.189 --> 00:06:07.868 without compromising speed too much. -00:06:12.320 --> 00:06:15.159 +00:06:07.869 --> 00:06:10.708 Yes. Once I had the representation, -00:06:15.160 --> 00:06:18.079 +00:06:10.709 --> 00:06:13.628 the scrambling itself should not be too hard. -00:06:18.080 --> 00:06:22.199 +00:06:13.629 --> 00:06:17.748 For this, it's important to consider that basically -00:06:22.200 --> 00:06:23.599 +00:06:17.749 --> 00:06:19.148 if you do a face turn -00:06:23.600 --> 00:06:26.879 +00:06:19.149 --> 00:06:22.428 you end up swapping some facelets with other facelets, -00:06:26.880 --> 00:06:30.479 +00:06:22.429 --> 00:06:26.028 that's the easiest way to think about this. -00:06:30.480 --> 00:06:33.719 +00:06:26.029 --> 00:06:29.268 To determine which one goes into which one's position, -00:06:33.720 --> 00:06:36.921 +00:06:29.269 --> 00:06:32.470 it was pretty confusing to figure this out. -00:06:36.922 --> 00:06:38.759 +00:06:32.471 --> 00:06:34.308 For this I went through a few papers, -00:06:38.760 --> 00:06:40.479 +00:06:34.309 --> 00:06:36.028 and I found one which suggested -00:06:40.480 --> 00:06:42.399 +00:06:36.029 --> 00:06:37.948 to just build a cube out of paper, -00:06:42.400 --> 00:06:44.479 +00:06:37.949 --> 00:06:40.028 number every facelet, and turn it -00:06:44.480 --> 00:06:48.799 +00:06:40.029 --> 00:06:44.348 and keep track of which facelet moved into which position. -00:06:48.800 --> 00:06:51.959 +00:06:44.349 --> 00:06:47.508 And programmatically, the `cl-rotatef` macro -00:06:51.960 --> 00:06:53.839 +00:06:47.509 --> 00:06:49.388 was very, very useful for doing this kind of -00:06:53.840 --> 00:06:56.079 +00:06:49.389 --> 00:06:51.628 in-place swapping you need for this operation. -00:06:56.080 --> 00:06:59.319 +00:06:51.629 --> 00:06:54.868 So in the future, group theory would hopefully -00:06:59.320 --> 00:07:02.439 +00:06:54.869 --> 00:06:57.988 make this a bit less awkward. -00:07:02.440 --> 00:07:04.559 +00:06:57.989 --> 00:07:00.108 Here's a photo of this paper cube I made -00:07:04.560 --> 00:07:08.319 +00:07:00.109 --> 00:07:03.868 along with a real cube. As you can see -00:07:08.320 --> 00:07:11.799 +00:07:03.869 --> 00:07:07.348 mathematically speaking, they are the same thing, -00:07:11.800 --> 00:07:13.719 +00:07:07.349 --> 00:07:09.268 they just look very, very different. NOTE Scrambling -00:07:13.720 --> 00:07:18.759 +00:07:09.269 --> 00:07:14.308 So the scramble algorithm itself, -00:07:18.760 --> 00:07:23.879 +00:07:14.309 --> 00:07:19.428 I pondered how this would even be done. In the competitions, -00:07:23.880 --> 00:07:26.039 +00:07:19.429 --> 00:07:21.588 They do this in a very, very elaborate way. -00:07:26.040 --> 00:07:27.199 +00:07:21.589 --> 00:07:22.748 They generate a random cube, -00:07:27.200 --> 00:07:29.839 +00:07:22.749 --> 00:07:25.388 they try to solve it, and if it's solvable -00:07:29.840 --> 00:07:32.999 +00:07:25.389 --> 00:07:28.548 they use these solution moves -00:07:33.000 --> 00:07:35.279 +00:07:28.549 --> 00:07:30.828 to turn into a scramble basically. -00:07:35.280 --> 00:07:39.399 +00:07:30.829 --> 00:07:34.948 And they also make sure to canonicalize the moves, -00:07:39.400 --> 00:07:42.999 +00:07:34.949 --> 00:07:38.548 so if you have subsequent moves that can be simplified, -00:07:43.000 --> 00:07:45.039 +00:07:38.549 --> 00:07:40.588 they do simplify these as much as possible. -00:07:45.040 --> 00:07:45.679 +00:07:40.589 --> 00:07:41.228 For example, -00:07:45.680 --> 00:07:48.199 +00:07:41.229 --> 00:07:43.748 if you have two subsequent rotations in one direction, -00:07:48.200 --> 00:07:51.119 +00:07:43.749 --> 00:07:46.668 it's turned into a different kind of rotation, -00:07:51.120 --> 00:07:53.839 +00:07:46.669 --> 00:07:49.388 so 90 and 90 equals 180. -00:07:53.840 --> 00:07:57.759 +00:07:49.389 --> 00:07:53.308 And the other Elisp scramblers I looked at, -00:07:57.760 --> 00:07:59.559 +00:07:53.309 --> 00:07:55.108 they generate random moves. -00:07:59.560 --> 00:08:01.959 +00:07:55.109 --> 00:07:57.508 Some of them do canonicalize. Not all of them. -00:08:01.960 --> 00:08:05.359 +00:07:57.509 --> 00:08:00.908 This one tries to do the best low-fi thing, -00:08:05.360 --> 00:08:06.839 +00:08:00.909 --> 00:08:02.388 that is, generating random moves, -00:08:06.840 --> 00:08:08.479 +00:08:02.389 --> 00:08:04.028 canonicalizing and repeating -00:08:08.480 --> 00:08:13.999 +00:08:04.029 --> 00:08:09.548 until enough have been generated. NOTE Visualization -00:08:14.000 --> 00:08:17.599 +00:08:09.549 --> 00:08:13.148 For the visualization I had to figure out -00:08:17.600 --> 00:08:18.959 +00:08:13.149 --> 00:08:14.508 something else too complicated. -00:08:18.960 --> 00:08:21.679 +00:08:14.509 --> 00:08:17.228 For this, I tried to figure out -00:08:21.680 --> 00:08:24.319 +00:08:17.229 --> 00:08:19.868 where every facelift would end up in the puzzle view -00:08:24.320 --> 00:08:25.879 +00:08:19.869 --> 00:08:21.428 when you would unfold it. -00:08:25.880 --> 00:08:30.119 +00:08:21.429 --> 00:08:25.668 And for this, I did not consider the facelet orientation. -00:08:30.120 --> 00:08:33.719 +00:08:25.669 --> 00:08:29.268 This may be important later for some other puzzles -00:08:33.720 --> 00:08:35.599 +00:08:29.269 --> 00:08:31.148 where you can end up with very twisted faces, -00:08:35.600 --> 00:08:37.479 +00:08:31.149 --> 00:08:33.028 but for simple cubes, it's not a problem. -00:08:37.480 --> 00:08:40.759 +00:08:33.029 --> 00:08:36.308 My initial prototype used colored text, -00:08:40.760 --> 00:08:43.199 +00:08:36.309 --> 00:08:38.748 but later, I used the SVG library. -00:08:43.200 --> 00:08:46.039 +00:08:38.749 --> 00:08:41.588 It turned out to be easy enough to use, actually. -00:08:46.040 --> 00:08:50.559 +00:08:41.589 --> 00:08:46.108 Currently, I have hard-coded face-color mappings, -00:08:50.560 --> 00:08:53.559 +00:08:46.109 --> 00:08:49.108 but I plan to replace this so that theming is possible. -00:08:53.560 --> 00:08:56.039 +00:08:49.109 --> 00:08:51.588 For example, if you happen to have a cube -00:08:56.040 --> 00:08:59.140 +00:08:51.589 --> 00:08:54.689 that does not have the same color mappings as I do, -00:08:59.141 --> 00:09:00.919 +00:08:54.690 --> 00:08:56.468 then you should be able to fix this. NOTE UI with Transient -00:09:00.920 --> 00:09:05.879 +00:08:56.469 --> 00:09:01.428 Next challenge was to build -00:09:05.880 --> 00:09:08.399 +00:09:01.429 --> 00:09:03.948 a beautiful intuitive UI with Transient. -00:09:08.400 --> 00:09:11.319 +00:09:03.949 --> 00:09:06.868 The reason why I chose this is -00:09:11.320 --> 00:09:14.799 +00:09:06.869 --> 00:09:10.348 because it would be self-documenting and Magit-style, -00:09:14.800 --> 00:09:16.799 +00:09:10.349 --> 00:09:12.348 and everyone knows how Magit works basically. -00:09:16.800 --> 00:09:19.759 +00:09:12.349 --> 00:09:15.308 Since Transient has become part of Emacs, -00:09:19.760 --> 00:09:21.679 +00:09:15.309 --> 00:09:17.228 there is really no reason to not try it out. -00:09:21.680 --> 00:09:26.119 +00:09:17.229 --> 00:09:21.668 The problem was documentation is difficult to understand. -00:09:26.120 --> 00:09:27.839 +00:09:21.669 --> 00:09:23.388 It's very abstract and high level, -00:09:27.840 --> 00:09:30.319 +00:09:23.389 --> 00:09:25.868 and it's hard to figure out. "Okay, -00:09:30.320 --> 00:09:31.239 +00:09:25.869 --> 00:09:26.788 I want to do something, -00:09:31.240 --> 00:09:33.359 +00:09:26.789 --> 00:09:28.908 how am I supposed to do this?" -00:09:33.360 --> 00:09:37.799 +00:09:28.909 --> 00:09:33.348 I did find transient-showcase, which has lots of examples, -00:09:37.800 --> 00:09:40.079 +00:09:33.349 --> 00:09:35.628 but they don't really feel finished -00:09:40.080 --> 00:09:43.519 +00:09:35.629 --> 00:09:39.068 and not realistic enough. -00:09:43.520 --> 00:09:45.199 +00:09:39.069 --> 00:09:40.748 When I tried to use the package, -00:09:45.200 --> 00:09:47.359 +00:09:40.749 --> 00:09:42.908 I got plenty of unhelpful error messages -00:09:47.360 --> 00:09:48.559 +00:09:42.909 --> 00:09:44.108 when using it incorrectly. -00:09:48.560 --> 00:09:50.399 +00:09:44.109 --> 00:09:45.948 I did manage to figure it out, -00:09:50.400 --> 00:09:55.039 +00:09:45.949 --> 00:09:50.588 but I plan to find more actual examples of it, -00:09:55.040 --> 00:09:57.879 +00:09:50.589 --> 00:09:53.428 to have an executable reference basically -00:09:57.880 --> 00:10:00.079 +00:09:53.429 --> 00:09:55.628 and try to improve my use of it. NOTE Book-keeping with SQLite -00:10:00.080 --> 00:10:05.999 +00:09:55.629 --> 00:10:01.548 For the book-keeping, I used SQLite. -00:10:06.000 --> 00:10:08.999 +00:10:01.549 --> 00:10:04.548 This is a very recent addition to Emacs, -00:10:09.000 --> 00:10:11.759 +00:10:04.549 --> 00:10:07.308 it only appeared in the current major version. -00:10:11.760 --> 00:10:13.839 +00:10:07.309 --> 00:10:09.388 It's still very early days. -00:10:13.840 --> 00:10:17.479 +00:10:09.389 --> 00:10:13.028 I found some oddities, one of them turned out to be -00:10:17.480 --> 00:10:19.279 +00:10:13.029 --> 00:10:14.828 a bug in the transaction macro. -00:10:19.280 --> 00:10:22.039 +00:10:14.829 --> 00:10:17.588 Like basically, if you do an SQL transaction -00:10:22.040 --> 00:10:24.639 +00:10:17.589 --> 00:10:20.188 and an error happens, then every helper I found -00:10:24.640 --> 00:10:25.399 +00:10:20.189 --> 00:10:20.948 does a rollback on an error. -00:10:25.400 --> 00:10:31.199 +00:10:20.949 --> 00:10:26.748 But this one did not. It actually committed on an error, -00:10:31.200 --> 00:10:34.319 +00:10:26.749 --> 00:10:29.868 and this was very weird to figure out. -00:10:34.320 --> 00:10:38.759 +00:10:29.869 --> 00:10:34.308 I reported a bug. Eli was nice enough to send me a patch. -00:10:38.760 --> 00:10:39.879 +00:10:34.309 --> 00:10:35.428 We did some patch review, -00:10:39.880 --> 00:10:42.439 +00:10:35.429 --> 00:10:37.988 and he ended up fixing it properly. -00:10:42.440 --> 00:10:50.119 +00:10:37.989 --> 00:10:45.668 So yes, there's still a lot to be done there, and yeah, -00:10:50.120 --> 00:10:51.359 +00:10:45.669 --> 00:10:46.908 the API is very basic. -00:10:51.360 --> 00:10:53.359 +00:10:46.909 --> 00:10:48.908 You don't have convenience helpers -00:10:53.360 --> 00:10:55.759 +00:10:48.909 --> 00:10:51.308 like fetch the first row or fetch the first value -00:10:55.760 --> 00:10:58.880 +00:10:51.309 --> 00:10:54.429 or anything, but they're easy enough to write yourself. -00:10:58.881 --> 00:11:00.820 +00:10:54.430 --> 00:10:56.369 And the biggest challenge with this bookkeeping part -00:11:00.821 --> 00:11:02.479 +00:10:56.370 --> 00:10:58.028 was figuring out a decent schema, -00:11:02.480 --> 00:11:04.599 +00:10:58.029 --> 00:11:00.148 like how to organize data correctly -00:11:04.600 --> 00:11:06.799 +00:11:00.149 --> 00:11:02.348 so that it would not be awkward to manipulate. -00:11:06.800 --> 00:11:10.199 +00:11:02.349 --> 00:11:05.748 And with this, you can finally build a package -00:11:10.200 --> 00:11:11.839 +00:11:05.749 --> 00:11:07.388 that remembers its state properly -00:11:11.840 --> 00:11:14.919 +00:11:07.389 --> 00:11:10.468 and don't have to run into foot guns -00:11:14.920 --> 00:11:17.079 +00:11:10.469 --> 00:11:12.628 with Lisp-style serialization, deserialization. NOTE Conclusion -00:11:17.080 --> 00:11:22.639 +00:11:12.629 --> 00:11:18.188 So yes, that concludes it so far. -00:11:22.640 --> 00:11:26.639 +00:11:18.189 --> 00:11:22.188 So what did I learn from this exercise? -00:11:26.640 --> 00:11:28.959 +00:11:22.189 --> 00:11:24.508 Well, there are still plenty of packages -00:11:28.960 --> 00:11:30.039 +00:11:24.509 --> 00:11:25.588 for Emacs to be written. -00:11:30.040 --> 00:11:33.359 +00:11:25.589 --> 00:11:28.908 If you think everything you can think of -00:11:33.360 --> 00:11:35.799 +00:11:28.909 --> 00:11:31.348 or you need has already been written, well, guess what? -00:11:35.800 --> 00:11:36.239 +00:11:31.349 --> 00:11:31.788 No. -00:11:36.240 --> 00:11:38.495 +00:11:31.789 --> 00:11:34.044 These are still plenty of specialized things -00:11:38.496 --> 00:11:41.239 +00:11:34.045 --> 00:11:36.788 that could need your help. -00:11:41.240 --> 00:11:44.239 +00:11:36.789 --> 00:11:39.788 These cubes do not require advanced mathematics, -00:11:44.240 --> 00:11:45.599 +00:11:39.789 --> 00:11:41.148 contrary to what you may think. -00:11:45.600 --> 00:11:49.159 +00:11:41.149 --> 00:11:44.708 Yes, you can apply advanced mathematics to them -00:11:49.160 --> 00:11:51.919 +00:11:44.709 --> 00:11:47.468 if you want to, but you don't have to. -00:11:51.920 --> 00:11:55.439 +00:11:47.469 --> 00:11:50.988 What surprised me about this is basically group theory. -00:11:55.440 --> 00:11:56.519 +00:11:50.989 --> 00:11:52.068 I've heard of it before. -00:11:56.520 --> 00:11:58.279 +00:11:52.069 --> 00:11:53.828 It seemed to be a meme, basically, -00:11:58.280 --> 00:12:00.919 +00:11:53.829 --> 00:11:56.468 because it has been like mostly Haskell people -00:12:00.920 --> 00:12:02.639 +00:11:56.469 --> 00:11:58.188 being very excited about this -00:12:02.640 --> 00:12:06.959 +00:11:58.189 --> 00:12:02.508 and it seemed kind of, like, divorced from reality, basically. -00:12:06.960 --> 00:12:10.399 +00:12:02.509 --> 00:12:05.948 But this puzzle, it actually proves that yes, -00:12:10.400 --> 00:12:11.399 +00:12:05.949 --> 00:12:06.948 it has its use. -00:12:11.400 --> 00:12:12.879 +00:12:06.949 --> 00:12:08.428 It definitely has. -00:12:12.880 --> 00:12:15.839 +00:12:08.429 --> 00:12:11.388 You just have to find the right problem matching it, -00:12:15.840 --> 00:12:17.919 +00:12:11.389 --> 00:12:13.468 and yeah. -00:12:17.920 --> 00:12:19.839 +00:12:13.469 --> 00:12:15.388 So yeah, once I understand it better, -00:12:19.840 --> 00:12:22.999 +00:12:15.389 --> 00:12:18.548 the topic, I expect to write better code. -00:12:23.000 --> 00:12:28.919 +00:12:18.549 --> 00:12:24.468 These new Emacs features, they work well enough. -00:12:28.920 --> 00:12:30.359 +00:12:24.469 --> 00:12:25.908 There are some rough edges. -00:12:30.360 --> 00:12:31.879 +00:12:25.909 --> 00:12:27.428 They definitely need more testing. -00:12:31.880 --> 00:12:35.119 +00:12:27.429 --> 00:12:30.668 So please, please, everyone, -00:12:35.120 --> 00:12:38.999 +00:12:30.669 --> 00:12:34.548 if you write Elisp, please try SQLite or Transient -00:12:39.000 --> 00:12:41.159 +00:12:34.549 --> 00:12:36.708 or anything else that looks cool and shiny. -00:12:41.160 --> 00:12:42.919 +00:12:36.709 --> 00:12:38.468 Report bugs. -00:12:42.920 --> 00:12:46.039 +00:12:38.469 --> 00:12:41.588 Find ways to improve them, anything. And yeah, -00:12:46.040 --> 00:12:49.319 +00:12:41.589 --> 00:12:44.868 I'm sure that if we do this, -00:12:49.320 --> 00:12:52.119 +00:12:44.869 --> 00:12:47.668 then Emacs will continue to get even better. -00:12:52.120 --> 00:12:56.239 +00:12:47.669 --> 00:12:51.788 So yeah, what's next for this package? -00:12:56.240 --> 00:13:00.439 +00:12:51.789 --> 00:12:55.988 Well, I could... There are lots of obvious UI improvements -00:13:00.440 --> 00:13:01.799 +00:12:55.989 --> 00:12:57.348 and testing to be done. -00:13:01.800 --> 00:13:04.159 +00:12:57.349 --> 00:12:59.708 I basically want to reach feature parity -00:13:04.160 --> 00:13:06.879 +00:12:59.709 --> 00:13:02.428 with the twisty-timer app, which this is very much inspired by. -00:13:06.880 --> 00:13:11.119 +00:13:02.429 --> 00:13:06.668 I want nice-looking stats like graphical ones -00:13:11.120 --> 00:13:13.239 +00:13:06.669 --> 00:13:08.788 instead of just a simple list of times. -00:13:13.240 --> 00:13:15.679 +00:13:08.789 --> 00:13:11.228 And I want support for more puzzles, of course, -00:13:15.680 --> 00:13:16.999 +00:13:11.229 --> 00:13:12.548 not just the simple cubes, -00:13:17.000 --> 00:13:19.039 +00:13:12.549 --> 00:13:14.588 but as I progress learning these puzzles, -00:13:19.040 --> 00:13:22.519 +00:13:14.589 --> 00:13:18.068 I want to have Emacs supporting me for this. -00:13:22.520 --> 00:13:26.879 +00:13:18.069 --> 00:13:22.428 But generally, it's a very open-ended package. -00:13:26.880 --> 00:13:31.079 +00:13:22.429 --> 00:13:26.628 And this concludes the talk. -00:13:31.080 --> 00:13:35.360 +00:13:26.629 --> 00:13:30.909 Thank you very much. diff --git a/2023/info/cubing-after.md b/2023/info/cubing-after.md index cec619c1..6878ad92 100644 --- a/2023/info/cubing-after.md +++ b/2023/info/cubing-after.md @@ -86,183 +86,183 @@ [[!template new="1" text="""So at this point the organizer should hopefully show""" start="00:03:49.240" video="mainVideo-cubing" id="subtitle"]] [[!template text="""a small video I've prepared, a one minute video showing how""" start="00:03:54.200" video="mainVideo-cubing" id="subtitle"]] [[!template text="""I actually use this to solve a cube and to time my solve.""" start="00:03:58.000" video="mainVideo-cubing" id="subtitle"]] -[[!template new="1" text="""Okay, so building this thing, there were several challenges.""" start="00:05:19.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""The first one was how do I even represent""" start="00:05:22.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""the state of a Rubik's cube.""" start="00:05:24.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""For this there are many possible representations,""" start="00:05:26.920" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""no obvious best solution.""" start="00:05:29.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I did not, well, what helped me was that""" start="00:05:32.160" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I did not have to programmatically solve this thing,""" start="00:05:34.080" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""so I picked the easiest possible representation""" start="00:05:36.440" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""which is just an array of every single facelet.""" start="00:05:39.640" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""For a 3x3 cube you have 9 facelets on one side,""" start="00:05:42.720" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""so times 6 sides you would have 54 elements in this array.""" start="00:05:46.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So with this representation, it's very simple,""" start="00:05:51.720" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""but it's kind of weird to do scrambles with this.""" start="00:05:54.160" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""But otherwise, it worked very, very well.""" start="00:05:56.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""In the future, I plan to learn some group theory,""" start="00:05:59.360" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""pick a better representation""" start="00:06:01.720" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and do this in a much, much more elegant way""" start="00:06:03.200" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""without compromising speed too much.""" start="00:06:05.640" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Yes. Once I had the representation,""" start="00:06:12.320" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""the scrambling itself should not be too hard.""" start="00:06:15.160" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""For this, it's important to consider that basically""" start="00:06:18.080" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""if you do a face turn""" start="00:06:22.200" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""you end up swapping some facelets with other facelets,""" start="00:06:23.600" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""that's the easiest way to think about this.""" start="00:06:26.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""To determine which one goes into which one's position,""" start="00:06:30.480" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""it was pretty confusing to figure this out.""" start="00:06:33.720" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""For this I went through a few papers,""" start="00:06:36.922" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and I found one which suggested""" start="00:06:38.760" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""to just build a cube out of paper,""" start="00:06:40.480" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""number every facelet, and turn it""" start="00:06:42.400" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and keep track of which facelet moved into which position.""" start="00:06:44.480" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""And programmatically, the `cl-rotatef` macro""" start="00:06:48.800" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""was very, very useful for doing this kind of""" start="00:06:51.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""in-place swapping you need for this operation.""" start="00:06:53.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So in the future, group theory would hopefully""" start="00:06:56.080" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""make this a bit less awkward.""" start="00:06:59.320" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Here's a photo of this paper cube I made""" start="00:07:02.440" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""along with a real cube. As you can see""" start="00:07:04.560" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""mathematically speaking, they are the same thing,""" start="00:07:08.320" video="mainVideo-cubing" id="subtitle"]] -[[!template new="1" text="""they just look very, very different.""" start="00:07:11.800" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So the scramble algorithm itself,""" start="00:07:13.720" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I pondered how this would even be done. In the competitions,""" start="00:07:18.760" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""They do this in a very, very elaborate way.""" start="00:07:23.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""They generate a random cube,""" start="00:07:26.040" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""they try to solve it, and if it's solvable""" start="00:07:27.200" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""they use these solution moves""" start="00:07:29.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""to turn into a scramble basically.""" start="00:07:33.000" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""And they also make sure to canonicalize the moves,""" start="00:07:35.280" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""so if you have subsequent moves that can be simplified,""" start="00:07:39.400" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""they do simplify these as much as possible.""" start="00:07:43.000" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""For example,""" start="00:07:45.040" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""if you have two subsequent rotations in one direction,""" start="00:07:45.680" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""it's turned into a different kind of rotation,""" start="00:07:48.200" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""so 90 and 90 equals 180.""" start="00:07:51.120" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""And the other Elisp scramblers I looked at,""" start="00:07:53.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""they generate random moves.""" start="00:07:57.760" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Some of them do canonicalize. Not all of them.""" start="00:07:59.560" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""This one tries to do the best low-fi thing,""" start="00:08:01.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""that is, generating random moves,""" start="00:08:05.360" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""canonicalizing and repeating""" start="00:08:06.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""until enough have been generated.""" start="00:08:08.480" video="mainVideo-cubing" id="subtitle"]] -[[!template new="1" text="""For the visualization I had to figure out""" start="00:08:14.000" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""something else too complicated.""" start="00:08:17.600" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""For this, I tried to figure out""" start="00:08:18.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""where every facelift would end up in the puzzle view""" start="00:08:21.680" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""when you would unfold it.""" start="00:08:24.320" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""And for this, I did not consider the facelet orientation.""" start="00:08:25.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""This may be important later for some other puzzles""" start="00:08:30.120" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""where you can end up with very twisted faces,""" start="00:08:33.720" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""but for simple cubes, it's not a problem.""" start="00:08:35.600" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""My initial prototype used colored text,""" start="00:08:37.480" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""but later, I used the SVG library.""" start="00:08:40.760" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""It turned out to be easy enough to use, actually.""" start="00:08:43.200" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Currently, I have hard-coded face-color mappings,""" start="00:08:46.040" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""but I plan to replace this so that theming is possible.""" start="00:08:50.560" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""For example, if you happen to have a cube""" start="00:08:53.560" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""that does not have the same color mappings as I do,""" start="00:08:56.040" video="mainVideo-cubing" id="subtitle"]] -[[!template new="1" text="""then you should be able to fix this.""" start="00:08:59.141" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Next challenge was to build""" start="00:09:00.920" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""a beautiful intuitive UI with Transient.""" start="00:09:05.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""The reason why I chose this is""" start="00:09:08.400" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""because it would be self-documenting and Magit-style,""" start="00:09:11.320" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and everyone knows how Magit works basically.""" start="00:09:14.800" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Since Transient has become part of Emacs,""" start="00:09:16.800" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""there is really no reason to not try it out.""" start="00:09:19.760" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""The problem was documentation is difficult to understand.""" start="00:09:21.680" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""It's very abstract and high level,""" start="00:09:26.120" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and it's hard to figure out. "Okay,""" start="00:09:27.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I want to do something,""" start="00:09:30.320" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""how am I supposed to do this?"""" start="00:09:31.240" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I did find transient-showcase, which has lots of examples,""" start="00:09:33.360" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""but they don't really feel finished""" start="00:09:37.800" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and not realistic enough.""" start="00:09:40.080" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""When I tried to use the package,""" start="00:09:43.520" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I got plenty of unhelpful error messages""" start="00:09:45.200" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""when using it incorrectly.""" start="00:09:47.360" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I did manage to figure it out,""" start="00:09:48.560" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""but I plan to find more actual examples of it,""" start="00:09:50.400" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""to have an executable reference basically""" start="00:09:55.040" video="mainVideo-cubing" id="subtitle"]] -[[!template new="1" text="""and try to improve my use of it.""" start="00:09:57.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""For the book-keeping, I used SQLite.""" start="00:10:00.080" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""This is a very recent addition to Emacs,""" start="00:10:06.000" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""it only appeared in the current major version.""" start="00:10:09.000" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""It's still very early days.""" start="00:10:11.760" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I found some oddities, one of them turned out to be""" start="00:10:13.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""a bug in the transaction macro.""" start="00:10:17.480" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Like basically, if you do an SQL transaction""" start="00:10:19.280" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and an error happens, then every helper I found""" start="00:10:22.040" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""does a rollback on an error.""" start="00:10:24.640" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""But this one did not. It actually committed on an error,""" start="00:10:25.400" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and this was very weird to figure out.""" start="00:10:31.200" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I reported a bug. Eli was nice enough to send me a patch.""" start="00:10:34.320" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""We did some patch review,""" start="00:10:38.760" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and he ended up fixing it properly.""" start="00:10:39.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So yes, there's still a lot to be done there, and yeah,""" start="00:10:42.440" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""the API is very basic.""" start="00:10:50.120" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""You don't have convenience helpers""" start="00:10:51.360" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""like fetch the first row or fetch the first value""" start="00:10:53.360" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""or anything, but they're easy enough to write yourself.""" start="00:10:55.760" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""And the biggest challenge with this bookkeeping part""" start="00:10:58.881" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""was figuring out a decent schema,""" start="00:11:00.821" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""like how to organize data correctly""" start="00:11:02.480" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""so that it would not be awkward to manipulate.""" start="00:11:04.600" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""And with this, you can finally build a package""" start="00:11:06.800" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""that remembers its state properly""" start="00:11:10.200" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and don't have to run into foot guns""" start="00:11:11.840" video="mainVideo-cubing" id="subtitle"]] -[[!template new="1" text="""with Lisp-style serialization, deserialization.""" start="00:11:14.920" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So yes, that concludes it so far.""" start="00:11:17.080" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So what did I learn from this exercise?""" start="00:11:22.640" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Well, there are still plenty of packages""" start="00:11:26.640" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""for Emacs to be written.""" start="00:11:28.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""If you think everything you can think of""" start="00:11:30.040" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""or you need has already been written, well, guess what?""" start="00:11:33.360" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""No.""" start="00:11:35.800" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""These are still plenty of specialized things""" start="00:11:36.240" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""that could need your help.""" start="00:11:38.496" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""These cubes do not require advanced mathematics,""" start="00:11:41.240" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""contrary to what you may think.""" start="00:11:44.240" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Yes, you can apply advanced mathematics to them""" start="00:11:45.600" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""if you want to, but you don't have to.""" start="00:11:49.160" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""What surprised me about this is basically group theory.""" start="00:11:51.920" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I've heard of it before.""" start="00:11:55.440" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""It seemed to be a meme, basically,""" start="00:11:56.520" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""because it has been like mostly Haskell people""" start="00:11:58.280" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""being very excited about this""" start="00:12:00.920" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and it seemed kind of, like, divorced from reality, basically.""" start="00:12:02.640" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""But this puzzle, it actually proves that yes,""" start="00:12:06.960" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""it has its use.""" start="00:12:10.400" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""It definitely has.""" start="00:12:11.400" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""You just have to find the right problem matching it,""" start="00:12:12.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and yeah.""" start="00:12:15.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So yeah, once I understand it better,""" start="00:12:17.920" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""the topic, I expect to write better code.""" start="00:12:19.840" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""These new Emacs features, they work well enough.""" start="00:12:23.000" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""There are some rough edges.""" start="00:12:28.920" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""They definitely need more testing.""" start="00:12:30.360" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So please, please, everyone,""" start="00:12:31.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""if you write Elisp, please try SQLite or Transient""" start="00:12:35.120" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""or anything else that looks cool and shiny.""" start="00:12:39.000" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Report bugs.""" start="00:12:41.160" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Find ways to improve them, anything. And yeah,""" start="00:12:42.920" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I'm sure that if we do this,""" start="00:12:46.040" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""then Emacs will continue to get even better.""" start="00:12:49.320" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""So yeah, what's next for this package?""" start="00:12:52.120" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Well, I could... There are lots of obvious UI improvements""" start="00:12:56.240" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""and testing to be done.""" start="00:13:00.440" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I basically want to reach feature parity""" start="00:13:01.800" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""with the twisty-timer app, which this is very much inspired by.""" start="00:13:04.160" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I want nice-looking stats like graphical ones""" start="00:13:06.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""instead of just a simple list of times.""" start="00:13:11.120" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""And I want support for more puzzles, of course,""" start="00:13:13.240" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""not just the simple cubes,""" start="00:13:15.680" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""but as I progress learning these puzzles,""" start="00:13:17.000" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""I want to have Emacs supporting me for this.""" start="00:13:19.040" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""But generally, it's a very open-ended package.""" start="00:13:22.520" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""And this concludes the talk.""" start="00:13:26.880" video="mainVideo-cubing" id="subtitle"]] -[[!template text="""Thank you very much.""" start="00:13:31.080" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Okay, so building this thing, there were several challenges.""" start="00:05:15.240" video="mainVideo-cubing" id="subtitle"]] +[[!template new="1" text="""The first one was how do I even represent""" start="00:05:18.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""the state of a Rubik's cube.""" start="00:05:20.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""For this there are many possible representations,""" start="00:05:22.469" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""no obvious best solution.""" start="00:05:25.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I did not, well, what helped me was that""" start="00:05:27.709" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I did not have to programmatically solve this thing,""" start="00:05:29.629" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""so I picked the easiest possible representation""" start="00:05:31.989" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""which is just an array of every single facelet.""" start="00:05:35.189" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""For a 3x3 cube you have 9 facelets on one side,""" start="00:05:38.269" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""so times 6 sides you would have 54 elements in this array.""" start="00:05:42.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""So with this representation, it's very simple,""" start="00:05:47.269" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""but it's kind of weird to do scrambles with this.""" start="00:05:49.709" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""But otherwise, it worked very, very well.""" start="00:05:52.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""In the future, I plan to learn some group theory,""" start="00:05:54.909" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""pick a better representation""" start="00:05:57.269" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and do this in a much, much more elegant way""" start="00:05:58.749" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""without compromising speed too much.""" start="00:06:01.189" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Yes. Once I had the representation,""" start="00:06:07.869" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""the scrambling itself should not be too hard.""" start="00:06:10.709" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""For this, it's important to consider that basically""" start="00:06:13.629" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""if you do a face turn""" start="00:06:17.749" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""you end up swapping some facelets with other facelets,""" start="00:06:19.149" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""that's the easiest way to think about this.""" start="00:06:22.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""To determine which one goes into which one's position,""" start="00:06:26.029" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""it was pretty confusing to figure this out.""" start="00:06:29.269" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""For this I went through a few papers,""" start="00:06:32.471" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and I found one which suggested""" start="00:06:34.309" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""to just build a cube out of paper,""" start="00:06:36.029" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""number every facelet, and turn it""" start="00:06:37.949" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and keep track of which facelet moved into which position.""" start="00:06:40.029" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""And programmatically, the `cl-rotatef` macro""" start="00:06:44.349" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""was very, very useful for doing this kind of""" start="00:06:47.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""in-place swapping you need for this operation.""" start="00:06:49.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""So in the future, group theory would hopefully""" start="00:06:51.629" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""make this a bit less awkward.""" start="00:06:54.869" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Here's a photo of this paper cube I made""" start="00:06:57.989" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""along with a real cube. As you can see""" start="00:07:00.109" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""mathematically speaking, they are the same thing,""" start="00:07:03.869" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""they just look very, very different.""" start="00:07:07.349" video="mainVideo-cubing" id="subtitle"]] +[[!template new="1" text="""So the scramble algorithm itself,""" start="00:07:09.269" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I pondered how this would even be done. In the competitions,""" start="00:07:14.309" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""They do this in a very, very elaborate way.""" start="00:07:19.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""They generate a random cube,""" start="00:07:21.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""they try to solve it, and if it's solvable""" start="00:07:22.749" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""they use these solution moves""" start="00:07:25.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""to turn into a scramble basically.""" start="00:07:28.549" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""And they also make sure to canonicalize the moves,""" start="00:07:30.829" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""so if you have subsequent moves that can be simplified,""" start="00:07:34.949" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""they do simplify these as much as possible.""" start="00:07:38.549" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""For example,""" start="00:07:40.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""if you have two subsequent rotations in one direction,""" start="00:07:41.229" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""it's turned into a different kind of rotation,""" start="00:07:43.749" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""so 90 and 90 equals 180.""" start="00:07:46.669" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""And the other Elisp scramblers I looked at,""" start="00:07:49.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""they generate random moves.""" start="00:07:53.309" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Some of them do canonicalize. Not all of them.""" start="00:07:55.109" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""This one tries to do the best low-fi thing,""" start="00:07:57.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""that is, generating random moves,""" start="00:08:00.909" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""canonicalizing and repeating""" start="00:08:02.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""until enough have been generated.""" start="00:08:04.029" video="mainVideo-cubing" id="subtitle"]] +[[!template new="1" text="""For the visualization I had to figure out""" start="00:08:09.549" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""something else too complicated.""" start="00:08:13.149" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""For this, I tried to figure out""" start="00:08:14.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""where every facelift would end up in the puzzle view""" start="00:08:17.229" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""when you would unfold it.""" start="00:08:19.869" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""And for this, I did not consider the facelet orientation.""" start="00:08:21.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""This may be important later for some other puzzles""" start="00:08:25.669" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""where you can end up with very twisted faces,""" start="00:08:29.269" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""but for simple cubes, it's not a problem.""" start="00:08:31.149" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""My initial prototype used colored text,""" start="00:08:33.029" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""but later, I used the SVG library.""" start="00:08:36.309" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""It turned out to be easy enough to use, actually.""" start="00:08:38.749" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Currently, I have hard-coded face-color mappings,""" start="00:08:41.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""but I plan to replace this so that theming is possible.""" start="00:08:46.109" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""For example, if you happen to have a cube""" start="00:08:49.109" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""that does not have the same color mappings as I do,""" start="00:08:51.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""then you should be able to fix this.""" start="00:08:54.690" video="mainVideo-cubing" id="subtitle"]] +[[!template new="1" text="""Next challenge was to build""" start="00:08:56.469" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""a beautiful intuitive UI with Transient.""" start="00:09:01.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""The reason why I chose this is""" start="00:09:03.949" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""because it would be self-documenting and Magit-style,""" start="00:09:06.869" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and everyone knows how Magit works basically.""" start="00:09:10.349" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Since Transient has become part of Emacs,""" start="00:09:12.349" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""there is really no reason to not try it out.""" start="00:09:15.309" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""The problem was documentation is difficult to understand.""" start="00:09:17.229" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""It's very abstract and high level,""" start="00:09:21.669" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and it's hard to figure out. "Okay,""" start="00:09:23.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I want to do something,""" start="00:09:25.869" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""how am I supposed to do this?"""" start="00:09:26.789" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I did find transient-showcase, which has lots of examples,""" start="00:09:28.909" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""but they don't really feel finished""" start="00:09:33.349" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and not realistic enough.""" start="00:09:35.629" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""When I tried to use the package,""" start="00:09:39.069" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I got plenty of unhelpful error messages""" start="00:09:40.749" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""when using it incorrectly.""" start="00:09:42.909" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I did manage to figure it out,""" start="00:09:44.109" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""but I plan to find more actual examples of it,""" start="00:09:45.949" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""to have an executable reference basically""" start="00:09:50.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and try to improve my use of it.""" start="00:09:53.429" video="mainVideo-cubing" id="subtitle"]] +[[!template new="1" text="""For the book-keeping, I used SQLite.""" start="00:09:55.629" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""This is a very recent addition to Emacs,""" start="00:10:01.549" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""it only appeared in the current major version.""" start="00:10:04.549" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""It's still very early days.""" start="00:10:07.309" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I found some oddities, one of them turned out to be""" start="00:10:09.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""a bug in the transaction macro.""" start="00:10:13.029" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Like basically, if you do an SQL transaction""" start="00:10:14.829" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and an error happens, then every helper I found""" start="00:10:17.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""does a rollback on an error.""" start="00:10:20.189" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""But this one did not. It actually committed on an error,""" start="00:10:20.949" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and this was very weird to figure out.""" start="00:10:26.749" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I reported a bug. Eli was nice enough to send me a patch.""" start="00:10:29.869" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""We did some patch review,""" start="00:10:34.309" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and he ended up fixing it properly.""" start="00:10:35.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""So yes, there's still a lot to be done there, and yeah,""" start="00:10:37.989" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""the API is very basic.""" start="00:10:45.669" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""You don't have convenience helpers""" start="00:10:46.909" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""like fetch the first row or fetch the first value""" start="00:10:48.909" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""or anything, but they're easy enough to write yourself.""" start="00:10:51.309" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""And the biggest challenge with this bookkeeping part""" start="00:10:54.430" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""was figuring out a decent schema,""" start="00:10:56.370" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""like how to organize data correctly""" start="00:10:58.029" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""so that it would not be awkward to manipulate.""" start="00:11:00.149" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""And with this, you can finally build a package""" start="00:11:02.349" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""that remembers its state properly""" start="00:11:05.749" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and don't have to run into foot guns""" start="00:11:07.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""with Lisp-style serialization, deserialization.""" start="00:11:10.469" video="mainVideo-cubing" id="subtitle"]] +[[!template new="1" text="""So yes, that concludes it so far.""" start="00:11:12.629" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""So what did I learn from this exercise?""" start="00:11:18.189" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Well, there are still plenty of packages""" start="00:11:22.189" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""for Emacs to be written.""" start="00:11:24.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""If you think everything you can think of""" start="00:11:25.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""or you need has already been written, well, guess what?""" start="00:11:28.909" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""No.""" start="00:11:31.349" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""These are still plenty of specialized things""" start="00:11:31.789" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""that could need your help.""" start="00:11:34.045" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""These cubes do not require advanced mathematics,""" start="00:11:36.789" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""contrary to what you may think.""" start="00:11:39.789" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Yes, you can apply advanced mathematics to them""" start="00:11:41.149" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""if you want to, but you don't have to.""" start="00:11:44.709" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""What surprised me about this is basically group theory.""" start="00:11:47.469" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I've heard of it before.""" start="00:11:50.989" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""It seemed to be a meme, basically,""" start="00:11:52.069" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""because it has been like mostly Haskell people""" start="00:11:53.829" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""being very excited about this""" start="00:11:56.469" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and it seemed kind of, like, divorced from reality, basically.""" start="00:11:58.189" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""But this puzzle, it actually proves that yes,""" start="00:12:02.509" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""it has its use.""" start="00:12:05.949" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""It definitely has.""" start="00:12:06.949" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""You just have to find the right problem matching it,""" start="00:12:08.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and yeah.""" start="00:12:11.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""So yeah, once I understand it better,""" start="00:12:13.469" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""the topic, I expect to write better code.""" start="00:12:15.389" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""These new Emacs features, they work well enough.""" start="00:12:18.549" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""There are some rough edges.""" start="00:12:24.469" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""They definitely need more testing.""" start="00:12:25.909" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""So please, please, everyone,""" start="00:12:27.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""if you write Elisp, please try SQLite or Transient""" start="00:12:30.669" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""or anything else that looks cool and shiny.""" start="00:12:34.549" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Report bugs.""" start="00:12:36.709" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Find ways to improve them, anything. And yeah,""" start="00:12:38.469" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I'm sure that if we do this,""" start="00:12:41.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""then Emacs will continue to get even better.""" start="00:12:44.869" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""So yeah, what's next for this package?""" start="00:12:47.669" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Well, I could... There are lots of obvious UI improvements""" start="00:12:51.789" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""and testing to be done.""" start="00:12:55.989" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I basically want to reach feature parity""" start="00:12:57.349" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""with the twisty-timer app, which this is very much inspired by.""" start="00:12:59.709" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I want nice-looking stats like graphical ones""" start="00:13:02.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""instead of just a simple list of times.""" start="00:13:06.669" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""And I want support for more puzzles, of course,""" start="00:13:08.789" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""not just the simple cubes,""" start="00:13:11.229" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""but as I progress learning these puzzles,""" start="00:13:12.549" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""I want to have Emacs supporting me for this.""" start="00:13:14.589" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""But generally, it's a very open-ended package.""" start="00:13:18.069" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""And this concludes the talk.""" start="00:13:22.429" video="mainVideo-cubing" id="subtitle"]] +[[!template text="""Thank you very much.""" start="00:13:26.629" video="mainVideo-cubing" id="subtitle"]] diff --git a/2023/info/cubing-before.md b/2023/info/cubing-before.md index 90f35134..76addede 100644 --- a/2023/info/cubing-before.md +++ b/2023/info/cubing-before.md @@ -1,7 +1,7 @@ The following image shows where the talk is in the schedule for Sun 2023-12-03. Solid lines show talks with Q&A via BigBlueButton. Dashed lines show talks with Q&A via IRC or Etherpad.
- Schedule for Sunday Sunday 8:59- 9:04 Sunday opening remarks sun-open 9:05- 9:25 Top 10 ways Hyperbole amps up Emacs hyperamp 9:40-10:00 Using Koutline for stream of thought journaling koutline 10:10-10:25 Parallel text replacement parallel 10:35-10:45 Eat and Eat powered Eshell, fast featureful terminal inside Emacs eat 11:00-11:20 The browser in a buffer poltys 11:35-11:55 Speedcubing in Emacs cubing 1:00- 1:40 Emacs MultiMedia System (EMMS) emms 1:55- 2:25 Programming with steno steno 2:35- 2:45 Mentoring VS-Coders as an Emacsian (or How to show not tell people about the wonders of Emacs) mentor 3:10- 3:40 Emacs saves the Web (maybe) web 3:55- 4:15 Sharing Emacs is Caring Emacs: Emacs education and why I embraced video sharing 4:30- 4:40 Sunday closing remarks sun-close 10:00-10:20 Bringing joy to Scheme programming scheme 10:35-10:55 GNU Emacs: A World of Possibilities world 11:10-11:20 A modern Emacs look-and-feel without pain flat 11:35-11:55 The Emacsen family, the design of an Emacs and the importance of Lisp emacsen 1:00- 1:35 emacs-gc-stats: Does garbage collection actually slow down Emacs? gc 1:50- 2:30 hyperdrive.el: Peer-to-peer filesystem in Emacs hyperdrive 2:45- 3:00 Writing a language server in OCaml for Emacs, fun, and profit lspocaml 3:15- 3:45 What I learned by writing test cases for GNU Hyperbole test 4:00- 4:20 EmacsConf.org: How we use Org Mode and TRAMP to organize and run a multi-track conference emacsconf 9 AM 10 AM 11 AM 12 PM 1 PM 2 PM 3 PM 4 PM 5 PM + Schedule for Sunday Sunday 8:59- 9:04 Sunday opening remarks sun-open 9:05- 9:25 Top 10 ways Hyperbole amps up Emacs hyperamp 9:40-10:00 Using Koutline for stream of thought journaling koutline 10:10-10:25 Parallel text replacement parallel 10:35-10:45 Eat and Eat powered Eshell, fast featureful terminal inside Emacs eat 11:00-11:20 The browser in a buffer poltys 11:35-11:55 Speedcubing in Emacs cubing 1:00- 1:40 Emacs MultiMedia System (EMMS) emms 1:55- 2:25 Programming with steno steno 2:35- 2:45 Mentoring VS-Coders as an Emacsian (or How to show not tell people about the wonders of Emacs) mentor 3:10- 3:40 Emacs saves the Web (maybe) web 3:55- 4:15 Sharing Emacs is Caring Emacs: Emacs education and why I embraced video sharing 4:30- 4:40 Sunday closing remarks sun-close 3:00- 3:10 The many ways to browse Hacker News from Emacs hn 4:00- 4:20 EmacsConf.org: How we use Org Mode and TRAMP to organize and run a multi-track conference emacsconf 10:00-10:20 Bringing joy to Scheme programming scheme 10:35-10:55 GNU Emacs: A World of Possibilities world 11:10-11:20 A modern Emacs look-and-feel without pain flat 11:35-11:55 The Emacsen family, the design of an Emacs and the importance of Lisp emacsen 1:00- 1:35 emacs-gc-stats: Does garbage collection actually slow down Emacs? gc 1:50- 2:30 hyperdrive.el: Peer-to-peer filesystem in Emacs hyperdrive 2:45- 3:00 Writing a language server in OCaml for Emacs, fun, and profit lspocaml 3:15- 3:45 What I learned by writing test cases for GNU Hyperbole test 9 AM 10 AM 11 AM 12 PM 1 PM 2 PM 3 PM 4 PM 5 PM
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