安裝教程：https://rustlang-cn.org/office/rust/book/getting-started/ch01-01-installation.html
emacs rust:https://manenko.com/2016/08/03/setup-emacs-for-rust-development.html
emacs 支持rust的配置
注：
1、export PATH="$HOME/.cargo/bin:$PATH"加到文件.bashrc,
(exec-path-from-shell-initialize)加到emacs配置文件以解決:auto-save-buffer cant locate executable rustfmt；
2、(setq racer-rust-src-path "/home/wang/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/src")不能自動補全添加；
3、安裝racer到此網站：https://github.com/racer-rust/emacs-racer；
4、如果找不到racer添加：(setq racer-cmd "~/.cargo/bin/racer")；
;; rust part
;;(require 'package)
;;(add-to-list 'package-archives
;; '("melpa" . "https://melpa.org/packages/") t)
(package-initialize)
(package-refresh-contents)
(add-hook 'racer-mode-hook #'company-mode)
(require 'rust-mode)
(add-hook 'rust-mode-hook
(lambda () (setq indent-tabs-mode nil)))
(setq rust-format-on-save t)
(define-key rust-mode-map (kbd "C-c C-c") 'rust-run)
(add-hook 'rust-mode-hook 'cargo-minor-mode)
(add-hook 'rust-mode-hook #'racer-mode)
(add-hook 'racer-mode-hook #'eldoc-mode)
(define-key rust-mode-map (kbd "TAB") #'company-indent-or-complete-common)
(setq company-tooltip-align-annotations t)
(exec-path-from-shell-initialize)
(setq racer-rust-src-path "/home/wang/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/src")