From b927ea205b267364b930cb70f2124663b3f22b6c Mon Sep 17 00:00:00 2001 From: Drwhooooo <90264412+Drwhooooo@users.noreply.github.com> Date: Tue, 11 Apr 2023 08:09:13 +0800 Subject: [PATCH] =?UTF-8?q?=E8=AF=91=E6=96=87=E6=8F=90=E4=BA=A4=20-=20?= =?UTF-8?q?=E2=80=9C=E4=B8=80=E4=B8=AA=E6=9B=B4=E5=A5=BD=E7=9A=84=E8=A7=86?= =?UTF-8?q?=E9=A2=91=E7=A0=81=E5=A4=B4=E2=80=9D=EF=BC=88An=20even=20Better?= =?UTF-8?q?=20Video=20Wharf=EF=BC=89=20(#29086)?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * 申请翻译 ID: Drwhooooo 时间：2023/4/6 - 15:30 * 译文提交 - “一个更好的视频码头”（An Even Better Video Wharf） 译者ID : Drwhooooo * 译文提交 - “一个更好的视频码头”（An Even Better Video Wharf） 译者ID : Drwhooooo * Rename 目标语言/技术/20210111 an even better video wharf.md to translated/tech/20210111 an even better video wharf.md --------- Co-authored-by: Xingyu.Wang --- .../20210111 an even better video wharf.md | 121 ------------------ .../20210111 an even better video wharf.md | 121 ++++++++++++++++++ 2 files changed, 121 insertions(+), 121 deletions(-) delete mode 100644 sources/tech/20210111 an even better video wharf.md create mode 100644 translated/tech/20210111 an even better video wharf.md diff --git a/sources/tech/20210111 an even better video wharf.md b/sources/tech/20210111 an even better video wharf.md deleted file mode 100644 index e49835c6e2..0000000000 --- a/sources/tech/20210111 an even better video wharf.md +++ /dev/null @@ -1,121 +0,0 @@ -[#]: subject: "an even better video wharf" -[#]: via: "https://jao.io/blog/2021-01-11-an-even-better-video-wharf.html" -[#]: author: "jao https://jao.io" -[#]: collector: "lujun9972" -[#]: translator: "Drwhooooo" -[#]: reviewer: " " -[#]: publisher: " " -[#]: url: " " - -an even better video wharf -====== - -A couple of days ago, [i was writing][1] about [embark][2] and my first experiment defining a new embarking to play remote video streams. Omar Antolín Camarena, embark's author, has been kind enough to not only read it, but comment on a couple of significant improvements that i think well deserve this follow-up. - -First, you'll remember that we were defining a function to detect a video URL: - -``` - - (defun jao-video-finder () - "Check whether we're looking at a video URL. - Return (video-url . ) if so." - (when-let ((url (thing-at-point-url-at-point))) - (when (string-match-p jao-video-url-rx url) - (cons 'video-url url)))) - -``` - -Once we've got a non-null `url` value, even if it's not a video URL, it's still certainly a URL, and embark has a `url` category, so we could save a new parsing by the default URL finder by saying: - -``` - - (when-let ((url (thing-at-point-url-at-point))) - (cons (if (string-match-p jao-video-url-rx url) 'video-url 'url) url)) - -``` - -This has the potential drawback that we're overriding embark's finder, `embark-target-url-at-point`, and we might prefer to keep the latter. - -Turns out that we can do that thanks to embark's _target transformers_. One can add to `embark-transformers-alist` an arbitrary function to be applied to a target of any given category, and embark will apply its actions to the transformed value. Omar calls this process, very aptly, a refinement of the target; here's how we would do it: - -``` - - (defun jao-refine-url-type (url) - "Refine type of URL in case it is a video." - (cons (if (string-match-p jao-video-url-rx url) 'video-url 'url) url)) - - (add-to-list 'embark-transformer-alist '(url . jao-refine-url-type)) - -``` - -With this strategy, we don't need `jao-video-finder` at all, and it also makes lots of sense, conceptually, to have our `video-url` defined as a refinement rather than a new target[1][3]. Omar's second suggestion is also in line with this concept: surely we want all actions available for `url` also for our `video-url`, don't we? Well, that's exactly the reason why the `embark-define-keymap` macro we used to define our actions can inherit all the actions already defined in another keymap, using the `:parent` keyword[2][4]: - -``` - - (embark-define-keymap jao-video-url-map - "Actions on URLs pointing to remote video streams." - :parent embark-url-map - ("p" jao-play-video-url)) - - (add-to-list 'embark-keymap-alist '(video-url . jao-video-url-map)) - -``` - -It is worth noting that this ability to inherit a keymap is not really an embark add-on: vanilla Emacs keymaps already have it, via the standard function `set-keymap-parent`. You could actually define `jao-video-url-map` without using `embark-define-keymap` at all, and it'd work exactly the same. - -So, our code has become shorter and more featureful: thanks, Omar! - -### Footnotes: - -[1][5] - -There's a scenario where keeping jao-video-finder could make sense, namely, if we want to alter the URL detection function. For instance, i use emacs-w3m, and there often a URL is stored as a text property (the actual text being the link text). To retrieve the URL at point there, one needs to call `w3m-anchor`, and `embark-target-url-at-point` will miss it. For that scenario, i ended up writing (and using) `jao-video-finder` defined with: - -``` - - (when-let ((url (or (w3m-anchor) (thing-at-point-url-at-point)))) - (cons (if (string-match-p jao-video-url-rx url) 'video-url 'url) url)) - -``` - -Another way of accomplishing the same thing (with another tip of the hat to Omar) would be to add a specific finder for w3m anchors (and keep using the transformer for video-url): - -``` - - (defun jao-w3m-url-finder () - (when-let ((url (w3m-anchor))) - (cons 'url url))) - - (add-to-list 'embark-target-finders #'jao-w3m-url-finder) - -``` - -This way is more modular and, depending on your taste, more elegant. These functions are small and there's not a big difference between the two approaches, but if one keeps adding finders, things can easily get uglier with the former approach. - -[2][6] - -In my original example, i was adding also `browse-url` and `browse-url-firefox` to the video map. The former is no longer necessary, because it's already present in `embark-url-map`. If we wanted to make `browse-url-firefox` available to _all_ URLs, we could add it to `embark-url-map` (remember, embark's keymaps are just Emacs keymaps). That's yet another simple way of extending embark. - -[Tags][7]: [emacs][8] - --------------------------------------------------------------------------------- - -via: https://jao.io/blog/2021-01-11-an-even-better-video-wharf.html - -作者：[jao][a] -选题：[lujun9972][b] -译者：[译者ID](https://github.com/译者ID) -校对：[校对者ID](https://github.com/校对者ID) - -本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: https://jao.io -[b]: https://github.com/lujun9972 -[1]: https://jao.io/blog/2021-01-09-embarking-videos.html -[2]: https://github.com/oantolin/embark -[3]: tmp.VUqMT3Yft2#fn.1 -[4]: tmp.VUqMT3Yft2#fn.2 -[5]: tmp.VUqMT3Yft2#fnr.1 -[6]: tmp.VUqMT3Yft2#fnr.2 -[7]: https://jao.io/blog/tags.html -[8]: https://jao.io/blog/tag-emacs.html diff --git a/translated/tech/20210111 an even better video wharf.md b/translated/tech/20210111 an even better video wharf.md new file mode 100644 index 0000000000..10f1f7adae --- /dev/null +++ b/translated/tech/20210111 an even better video wharf.md @@ -0,0 +1,121 @@ +[#]: subject: "an even better video wharf" +[#]: via: "https://jao.io/blog/2021-01-11-an-even-better-video-wharf.html" +[#]: author: "jao https://jao.io" +[#]: collector: "lujun9972" +[#]: translator: "Drwhooooo" +[#]: reviewer: " " +[#]: publisher: " " +[#]: url: " " + +一个更好的视频码头 +====== + +几天前，[我在写][1] 有关 [embark][2] 的内容，我的第一设备为启动远程视频流设计了一个新的 embark。作为 embark 的作者，Omar Antolín Camarena，不仅阅读了这篇内容，还点评了一下我认为值得跟进的一些重大改进. + +首先，你应该记得我们曾定义过一个检测视频 URL 的函数： + +``` + + (defun jao-video-finder () + "Check whether we're looking at a video URL. + Return (video-url . ) if so." + (when-let ((url (thing-at-point-url-at-point))) + (when (string-match-p jao-video-url-rx url) + (cons 'video-url url)))) + +``` + +当我们得到了一个非空的 `url` 值，即便它不是一个视频链接，但它仍然是一个确切的 URL，并且 embark 已有了一个 `url` 类别，所以我们可以借助默认的 URL 寻检器存储一个新的句法分析,语句如下： + +``` + + (when-let ((url (thing-at-point-url-at-point))) + (cons (if (string-match-p jao-video-url-rx url) 'video-url 'url) url)) + +``` +这里有一个潜在的缺点就是：我们重写了 embark 的寻检器，`embark-target-url-at-point`，所以我们可能更愿意保留后者。 + +实际上多亏了 embark 的 _目标转换器_ 我们才能做成。我们可以在 `embark-transformers-alist` 中添加任意一个函数，应用于任何一个给定类别的目标，而 embark 会将其转换后的值应用于它的操作中。Omar 很贴切地把这个过程称为“目标的精化”;我们具体做法如下： + +``` + + (defun jao-refine-url-type (url) + "Refine type of URL in case it is a video." + (cons (if (string-match-p jao-video-url-rx url) 'video-url 'url) url)) + + (add-to-list 'embark-transformer-alist '(url . jao-refine-url-type)) + +``` + +通过这种策略，我们就不再需要 `jao-video-finder` 了，而且从概念上来说，我们的 `video-url` 应该被定义为一个精化操作而并非是一个目标[1][3]。Omar 的第二个提议也与这个概念相契合：想必我们都希望所有关于 `url` 和我们的 `video-url` 的操作都是可用的，不是吗？ +唔，这就是为什么我们用来定义行为的 `embark-define-keymap` 的宏可以通过使用关键字[2][4] `:parent` 继承其他键映射中已经定义的所有操作的原因： + +``` + + (embark-define-keymap jao-video-url-map + "Actions on URLs pointing to remote video streams." + :parent embark-url-map + ("p" jao-play-video-url)) + + (add-to-list 'embark-keymap-alist '(video-url . jao-video-url-map)) + +``` + +这种继承键映射的功能并非是 embark 的附属功能：vanilla Emacs 键映射通过标准函数 `set-keymap-parent` 已经搞定它了。你可以完全不用 `embark-define-keymap` 来定义 `jao-video-url-map`，工作原理是一样的。 + +这样，我们的代码就能够更短，特征更多：谢谢你，Omar! + +### 脚注： + +[1][5] + +在某些情况下，保留 jao-video-finder 是有意义的，即，如果我们想要改变检测 URL 的功能的话。例如，我在使用 emacs-w3m 的时候，经常有一个 URL 作为文本属性储存了起来(实际文本是个链接文本)。要通过那里检索 URL，就需要调用 `w3m-anchor`，而用 `embark-target-url-at-point` 就会错过它。对于这种情况，我最终编写(并使用)`jao-video-finder` 将其通过下文定义: + +``` + + (when-let ((url (or (w3m-anchor) (thing-at-point-url-at-point)))) + (cons (if (string-match-p jao-video-url-rx url) 'video-url 'url) url)) + +``` + +另一种达成同件事情的方式（再次向 Omar 致敬）便是为 w3m 的锚点放置一个特定的巡检器（且继续使用 video-url 的转换器）： + +``` + + (defun jao-w3m-url-finder () + (when-let ((url (w3m-anchor))) + (cons 'url url))) + + (add-to-list 'embark-target-finders #'jao-w3m-url-finder) + +``` + +这种方法更加模块化，并且取决于你们的喜好，且更加巧妙。这些功能都很小巧并且两种方法之间并没有太大的差别，但是如果其中某一种继续加入更多寻检器的话，前一种方法用起来来反而会让一切变得更糟。 + +[2][6] + +在我最开始的例子中，我在视频地图中还添加了 `browse-url` 和 `browse-url-firefox`。前一个已不再重要，因为它已经在 `embark-url-map` 中出现过了，如果我们想让 `browse-url-firefox` 对 _所有_ 的 URLs 可用,我们可以将其加入到 `embark-url-map` （谨记，embark 的键映射只是 Emacs 的键映射）。这是另一种扩展 embark 的简便方法。 + +[标签][7]: [emacs][8] + +-------------------------------------------------------------------------------- + +via: https://jao.io/blog/2021-01-11-an-even-better-video-wharf.html + +作者：[jao][a] +选题：[lujun9972][b] +译者：[Drwhooooo](https://github.com/Drwhooooo) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://jao.io +[b]: https://github.com/lujun9972 +[1]: https://jao.io/blog/2021-01-09-embarking-videos.html +[2]: https://github.com/oantolin/embark +[3]: tmp.VUqMT3Yft2#fn.1 +[4]: tmp.VUqMT3Yft2#fn.2 +[5]: tmp.VUqMT3Yft2#fnr.1 +[6]: tmp.VUqMT3Yft2#fnr.2 +[7]: https://jao.io/blog/tags.html +[8]: https://jao.io/blog/tag-emacs.html