首先要从melpa源获取package list(类似apt update)
$ kate ~/.emacs.d/init.el
(require 'package)
(add-to-list 'package-archives '("melpa" . "https://melpa.org/packages/") t)
(package-initialize)
(package-refresh-contents)
然后打开emacs安装rust-mode
M-x package-install(Enter) rust-mode(Enter)
然后继续安装lsp-mode package
then add (require 'rust-mode) (require 'lsp-mode) to init.el
装完rust-mode插件后就可以把init.el配置文件中package那4行注释掉，不然每次启动都要联网更新包的索引，启动emacs都要等好几秒
然而出现两个报错:
cause of the error in your initialization file
[LSP] Unable to autoconfigure company-mode
还是vscode+ra或Intellij-Rust够简单傻瓜无需配置好用，vscode就多写一个rust-analyzer.server.path的json配置项就好了
实在难以理解用lisp写lsp-mode的一堆配置，用json不香么