4 ms·

LSP as a protocol feels like somebody documented IDE features, then exposed those directly at the protocol level. It's absurd. When last I checked, I could re

LSP as a protocol feels like somebody documented IDE features, then exposed those directly at the protocol level. It's absurd. When last I checked, I could register a function to be used to apply syntax highlighting when the LSP server identifies a change, but you couldn't make any explicit queries against the known parts of the syntax. I wanted to query the LSP server to tell whether the point was currently located within a string, but as far as I could tell, the LSP server couldn't be queried for the syntax type. You can ask for "selection suggestions", you can ask for "semantic tokens" within a specific range, but you cannot ask for the semantic token containing a single specific point.

db48x 3y ago
That's exactly what LSP is. Notice that it was invented by Microsoft and it becomes a lot less surprising.
antoineMoPa 3y ago
VS Code can achieve much more performant editing with the same server, so there is no excuse for emacs to be slow.
- MereInterest 3y ago
  My experience is that VS Code has a tremendous amount of input lag, to the point that I need to wait for a search prompt to focus before I can start my query. Emacs, on the other hand, is incredibly responsive, and even when running over a slow SSH connection has properly buffered inputs so I don’t need to wait. Emacs can achieve much more performant editing with the same server, so there’s no excuse for VS Code to be so slow.
  - BaculumMeumEst 3y ago
    VS Code in its current state has no perceptible input latency on modern hardware, easily verifiable. If you invested the time to configure Emacs to mimic VS code's completion- instantaneous fuzzy autocompletion on every keystroke- the GUI would lock up every time autocompletion is engaged, i.e. the entire editor stutters on every keystroke, because the garbage collector is constantly blocking the UI thread. The performance limitations are widely known. It's the reason yyoncho, the creator of LSP-mode, forked Emacs to explore adding multithreading to address the issue [0]. But I can't see this being fixed anytime soon, because there are a fleet of intellectually dishonest zealots on the internet that refuse to acknowledge it's an issue, and will flame anyone who brings it up. As a result, when new users try out Emacs and see that the performance sucks, many of them will instantly uninstall and return to VS code, and the userbase suffers. [0] https://www.reddit.com/r/emacs/comments/ymrkyn/async_nonblocking_jsonrpc_or_lsp_performance/ https://www.reddit.com/r/emacs/comments/ymrkyn/async_nonbloc...
    - G3rn0ti 3y ago
      > instantaneous fuzzy autocompletion on every keystroke- the GUI would lock up every time autocompletion is engaged, I am using lsp-mode enhanced autocompletion (using company.el) and I have never observed such a problem. I set the autcompletion delay to 0.0 in my case and work on 1k LOC modules. If you enjoy VS code, I am glad for you. It is certainly a good editor. But don't post generalized slurs against Emacs if you obviously haven't used it for long. Performance issues can happen but that highly depends on the context. What combination of language server, language server client and what language is causing this? Edit: If you are new to "lsp-mode" and you have performance issues, take a look here: https://emacs-lsp.github.io/lsp-mode/page/performance/#json-native-serializationdeserialization https://emacs-lsp.github.io/lsp-mode/page/performance/#json-... Also consider trying other LSP servers if available. For popular languages there are usually several alternatives to choose from: https://langserver.org/ https://langserver.org/
      - BaculumMeumEst 3y ago
        I mentioned that bringing up performance issues will bring you insults and dismissal, and you saw fit to reply with: > I have never observed such a problem > don't post generalized slurs against Emacs > If you enjoy VS code, I am glad for you. > you obviously haven't used it for long I guess it did not occur to you that you are immediately proving my point. To answer your question, the context is literally every single language server. Not only with autocompletion delay to 0.0, but also setting the minimum prefix to 1, so that it activates on every keystroke; the default is 3. The fuzzy completion cannot be configured out of the box, of course, it requires another extension. I posted a thread with much detail on why it occurs. You can downplay all you'd like, but a non-issue does not spur a productive maintainer to fork the entire codebase to implement changes, or alternative clients (LSP-bridge) that manage out-of-process connections to servers in order to work around Elisp limitations.
        G3rn0ti 3y ago
        Well, Emacs has indeed a problem with blocking because it is single-threaded. To resolve that issue internally it also maintains an event loop being used to drive async. functions calls. But not all extensions leverage that yet. But I doubt the problem described in that reddit thread you cited is really caused by that. It sounds more likely the author of that Emacs fork experienced an issue with inter process communication. Who knows because there is no detailed context given. I am using "lsp-mode" for Javascript, Typescript (including React) and even on a huge Perl repository and I don't find it to be too slow for me. I am running a five year old mediocre laptop using Ubuntu. But perhaps I don't have the same standards as the author of that Emacs fork. > You can downplay all you'd like, but a non-issue does not spur a productive maintainer to fork the entire codebase to implement changes, or alternative clients (LSP-bridge) that manage out-of-process connections to servers in order to work around Elisp limitations. Well, it's an impressive feat, for sure. But I don't know anyone actually using that person's fork. So I wonder whether that really is such a huge problem as the author implies. And -- why do you care anyway since you seem to be happy using VSCode?
grumpyprole 3y ago
Similarly you cannot use LSP to query the type of a symbol, something I do all the time in OCaml and other typed languages.

db48x 3y ago

That's exactly what LSP is. Notice that it was invented by Microsoft and it becomes a lot less surprising.

antoineMoPa 3y ago

VS Code can achieve much more performant editing with the same server, so there is no excuse for emacs to be slow.

MereInterest 3y ago
My experience is that VS Code has a tremendous amount of input lag, to the point that I need to wait for a search prompt to focus before I can start my query. Emacs, on the other hand, is incredibly responsive, and even when running over a slow SSH connection has properly buffered inputs so I don’t need to wait. Emacs can achieve much more performant editing with the same server, so there’s no excuse for VS Code to be so slow.
- BaculumMeumEst 3y ago
  VS Code in its current state has no perceptible input latency on modern hardware, easily verifiable. If you invested the time to configure Emacs to mimic VS code's completion- instantaneous fuzzy autocompletion on every keystroke- the GUI would lock up every time autocompletion is engaged, i.e. the entire editor stutters on every keystroke, because the garbage collector is constantly blocking the UI thread. The performance limitations are widely known. It's the reason yyoncho, the creator of LSP-mode, forked Emacs to explore adding multithreading to address the issue [0]. But I can't see this being fixed anytime soon, because there are a fleet of intellectually dishonest zealots on the internet that refuse to acknowledge it's an issue, and will flame anyone who brings it up. As a result, when new users try out Emacs and see that the performance sucks, many of them will instantly uninstall and return to VS code, and the userbase suffers. [0] https://www.reddit.com/r/emacs/comments/ymrkyn/async_nonblocking_jsonrpc_or_lsp_performance/ https://www.reddit.com/r/emacs/comments/ymrkyn/async_nonbloc...
  - G3rn0ti 3y ago
    > instantaneous fuzzy autocompletion on every keystroke- the GUI would lock up every time autocompletion is engaged, I am using lsp-mode enhanced autocompletion (using company.el) and I have never observed such a problem. I set the autcompletion delay to 0.0 in my case and work on 1k LOC modules. If you enjoy VS code, I am glad for you. It is certainly a good editor. But don't post generalized slurs against Emacs if you obviously haven't used it for long. Performance issues can happen but that highly depends on the context. What combination of language server, language server client and what language is causing this? Edit: If you are new to "lsp-mode" and you have performance issues, take a look here: https://emacs-lsp.github.io/lsp-mode/page/performance/#json-native-serializationdeserialization https://emacs-lsp.github.io/lsp-mode/page/performance/#json-... Also consider trying other LSP servers if available. For popular languages there are usually several alternatives to choose from: https://langserver.org/ https://langserver.org/
    - BaculumMeumEst 3y ago
      I mentioned that bringing up performance issues will bring you insults and dismissal, and you saw fit to reply with: > I have never observed such a problem > don't post generalized slurs against Emacs > If you enjoy VS code, I am glad for you. > you obviously haven't used it for long I guess it did not occur to you that you are immediately proving my point. To answer your question, the context is literally every single language server. Not only with autocompletion delay to 0.0, but also setting the minimum prefix to 1, so that it activates on every keystroke; the default is 3. The fuzzy completion cannot be configured out of the box, of course, it requires another extension. I posted a thread with much detail on why it occurs. You can downplay all you'd like, but a non-issue does not spur a productive maintainer to fork the entire codebase to implement changes, or alternative clients (LSP-bridge) that manage out-of-process connections to servers in order to work around Elisp limitations.
      - G3rn0ti 3y ago
        Well, Emacs has indeed a problem with blocking because it is single-threaded. To resolve that issue internally it also maintains an event loop being used to drive async. functions calls. But not all extensions leverage that yet. But I doubt the problem described in that reddit thread you cited is really caused by that. It sounds more likely the author of that Emacs fork experienced an issue with inter process communication. Who knows because there is no detailed context given. I am using "lsp-mode" for Javascript, Typescript (including React) and even on a huge Perl repository and I don't find it to be too slow for me. I am running a five year old mediocre laptop using Ubuntu. But perhaps I don't have the same standards as the author of that Emacs fork. > You can downplay all you'd like, but a non-issue does not spur a productive maintainer to fork the entire codebase to implement changes, or alternative clients (LSP-bridge) that manage out-of-process connections to servers in order to work around Elisp limitations. Well, it's an impressive feat, for sure. But I don't know anyone actually using that person's fork. So I wonder whether that really is such a huge problem as the author implies. And -- why do you care anyway since you seem to be happy using VSCode?

grumpyprole 3y ago

Similarly you cannot use LSP to query the type of a symbol, something I do all the time in OCaml and other typed languages.