Emacs: update setup instructions

`lsp-mode` now has built-in configuration for zls, so the only
configuration that might be required is setting the location of the zls
executable (or placing it in the PATH).

`doom-emacs` has not updated to use the latest version of `lsp-mode`
yet, so its configuration cannot be simplified. However, I've updated
the snippet for configuration to avoid loading `lsp-mode` on startup,
which can cause significant slowdown to Emacs startup, and instead defer
loading it until it is required.

README.md

@@ -216,13 +216,12 @@ let g:LanguageClient_serverCommands = {
 - [zig mode](https://github.com/ziglang/zig-mode) is also useful
 
 ```elisp
-(require 'lsp)
+;; Setup lsp-mode as desired.
-(add-to-list 'lsp-language-id-configuration '(zig-mode . "zig"))
+;; See https://emacs-lsp.github.io/lsp-mode/page/installation/ for more information.
-(lsp-register-client
+(require 'lsp-mode)
-  (make-lsp-client
+
-    :new-connection (lsp-stdio-connection "<path to zls>")
+;; Either place zls in your PATH or add the following:
-    :major-modes '(zig-mode)
+(setq lsp-zig-zls-executable "<path to zls>")
-    :server-id 'zls))
 ```
 
 ### Doom Emacs
@@ -231,17 +230,17 @@ let g:LanguageClient_serverCommands = {
 - Install the [zig-mode](https://github.com/ziglang/zig-mode) package (add `(package! zig-mode)` to your `packages.el` file
 
 ```elisp
-(require 'lsp)
 (use-package! zig-mode
-  :hook ((zig-mode . lsp))
+  :hook ((zig-mode . lsp-deferred))
   :custom (zig-format-on-save nil)
-  :init
+  :config
+  (after! lsp-mode
     (add-to-list 'lsp-language-id-configuration '(zig-mode . "zig"))
     (lsp-register-client
       (make-lsp-client
         :new-connection (lsp-stdio-connection "<path to zls>")
         :major-modes '(zig-mode)
-    :server-id 'zls)))
+        :server-id 'zls))))
 ```
 
 ## Related Projects

build.zig

@@ -146,31 +146,26 @@ pub fn config(step: *std.build.Step) anyerror!void {
                 \\Zig mode (https://github.com/ziglang/zig-mode) is also useful!
                 \\Then, add the following to your emacs config:
                 \\
-                \\(require 'lsp)
+                \\(require 'lsp-mode)
-                \\(add-to-list 'lsp-language-id-configuration '(zig-mode . "zig"))
+                \\(setq lsp-zig-zls-executable "<path to zls>")
-                \\(lsp-register-client
-                \\  (make-lsp-client
-                \\    :new-connection (lsp-stdio-connection "<path to zls>")
-                \\    :major-modes '(zig-mode)
-                \\    :server-id 'zls))
             , .{});
         },
         .Doom => {
             std.debug.warn(
                 \\To use ZLS in Doom Emacs, enable the lsp module
-                \\And install the zig mode (https://github.com/ziglang/zig-mode) package by adding `(package! zig-mode)` to your packages.el file.
+                \\And install the `zig-mode` (https://github.com/ziglang/zig-mode) package by adding `(package! zig-mode)` to your packages.el file.
                 \\
-                \\(require 'lsp)
                 \\(use-package! zig-mode
-                \\  :hook ((zig-mode . lsp))
+                \\  :hook ((zig-mode . lsp-deferred))
                 \\  :custom (zig-format-on-save nil)
-                \\  :init
+                \\  :config
+                \\  (after! lsp-mode
                 \\    (add-to-list 'lsp-language-id-configuration '(zig-mode . "zig"))
                 \\    (lsp-register-client
                 \\      (make-lsp-client
                 \\        :new-connection (lsp-stdio-connection "<path to zls>")
                 \\        :major-modes '(zig-mode)
-                \\    :server-id 'zls)))
+                \\        :server-id 'zls))))
             , .{});
         },
         .Other => {