dap-mode VS eglot

GDB with gdb -i dap allows you to debug any language that GDB can debug from within Emacs' dap-mode: https://github.com/emacs-lsp/dap-mode

lsp's brother. One search away. https://github.com/emacs-lsp/dap-mode

Debug template for go subtest was just added: https://github.com/emacs-lsp/dap-mode/pull/704/

Debugging (kind of an IDE feature) is a little harder. Out of the box, Emacs can at least debug emacs-lisp (with built-in features) and C (via gdb integration). Beyond that, take a look at dap-mode for other language options. Similarly, take a look at lsp-mode or eglot for code completion, more advanced linting, etc.

At least for web development I believe eglot is strictly worse. It does not support running multiple servers (e.g. tsserver and eslint-ls) (https://github.com/joaotavora/eglot/issues/976) which is supported by lsp-mode and neovim's built-in lsp client. Also, it does not have any equivalent to dap-mode which is lsp-mode only. Although worth noting dap-mode is currently useless for js (https://github.com/emacs-lsp/dap-mode/issues/369).

Hi, as it seems EGlot will receive the blessing of inclusion into vanilla Emacs. That makes me wonder how I am supposed to use dap-mode at it swaps in lsp-mode as a dependency.

We will use dap-mode with the dap-gdb-lldb option here. Under the hood, it uses the debug adapter from the Native Debug VSCode extension. Configuring it is described on the dap-mode webpages. After we have configured dap-mode, we could in theory reuse the launch.json configurations from the VSCode related articles above. That will require that you also use lsp-mode, as dap-launch depends on the lsp-workspace-root function and will not resolve when lsp-mode is not used. I don't use lsp-mode with C (company-clang and company-c-headers provide what I need), so the next logical solution would be to create a debug template ourselves:

Hmm it does seem like Emacs is growing support for the Debug Adapter Protocol (DAP), the LSP-alike convention that allows language developers to build language-specific debuggers that tie into the VSCode UI: https://github.com/emacs-lsp/dap-mode

So, what do you need: - Language server for Python (lsp and lsp-ui) Use lsp-mode it's more reach with features at the moment https://emacs-lsp.github.io/lsp-mode/page/installation/ - Real-time program debugging (dap-mode) https://github.com/emacs-lsp/dap-mode

Seems like too much work and the issue has been closed and not reopened since 2018 sadly. It looks like it won't be happening any time soon. https://github.com/emacs-lsp/dap-mode/issues/2

Recently I stumbled upon this issue:

https://github.com/joaotavora/eglot/discussions/1127

I don't know enough about emacs and LSP to see the full picture, but it seems that both eglot's and corfu's maintainers, assumably very competent programmers, can't find a solution for this.

I only skimmed the thread. My understanding is that LSP dumps a long list of completion candidates at once and they can't decide a cache strategy that works well with existing code...?

It could be. There are unfixed issues with eglot and corfu, and sadly not a lot of willingness to investigate.

Eglot errors when I add new Python code blocks. The error disappears when I reconnect the language server, but the same happens again when I add a new code block. My "workaround" now is that before I start working on the .qmd file, I just add a bunch of Python code blocks (for which I also have a function) and then reconnect the language server again. This way I can start working for a while until I need to add more code blocks again.

This discussion has helped with some performance issues: https://github.com/joaotavora/eglot/discussions/993.

I guess eglot doesn't support it yet: https://github.com/joaotavora/eglot/pull/839

This is not by pure chance, João is the developer of the Eglot LSP client and the breadcrumbs from LSP-mode had been requested as a feature, but as far as I remember João thought rightfully that this could be an independent package, see https://github.com/joaotavora/eglot/discussions/988

A substantial section of the community is using corfu instead of company, but I wouldn't say company is out of date by any means. In emacs 29 eglot will be a built in, which might act as a replacement for lsp-mode depending on what functionality you need.

I am currently running emacs 29 (built from emacs-29 branch) which – according to https://github.com/joaotavora/eglot – should contain the latest eglot.

Yep. You can use flymake or flycheck for that in combination with eglot or lsp-mode.

See https://github.com/joaotavora/eglot#diagnostics

(I have reported this (that is, ElDoc missing docs for callable things at point, when Eglot is enabled) as an issue recently: First on GitHub-discussions https://github.com/joaotavora/eglot/discussions/1200, then on Debbugs https://debbugs.gnu.org/cgi/bugreport.cgi?bug=62687. But the threads are very long, so I don't recommend reading them.)