Add formatter and some other stuff

lang/lean.el

@@ -0,0 +1,30 @@
+;;; lean -- summary -*- lexical-binding: t; -*-
+;;; Commentary:
+;;; Code:
+
+(require '+custom-pkg-prog-mode "$HOME/.emacs.d/pkg/prog-mode.el")
+(require '+custom-pkg-flycheck "$HOME/.emacs.d/pkg/flycheck.el")
+
+(use-package lean4-mode
+  :straight (lean4-mode
+	           :type git
+	           :host github
+	           :repo "leanprover/lean4-mode"
+	           :files ("*.el" "data"))
+  :defer t)
+
+(defun activate-lean-mode ()
+  "All things for Lean mode."
+  (interactive)
+
+  ;; Run LSP
+  (lsp-deferred)
+
+  ;; Company list override
+  (add-to-list (make-local-variable 'company-backends)
+               '(company-capf company-yasnippet)))
+
+(add-hook 'lean4-mode-hook 'activate-lean-mode)
+
+(provide '+custom-lang-lean)
+;;; lean.el ends here