Add rust-mode support

modules/module-rust.el

@@ -0,0 +1,32 @@
+;;; module-rust.el
+
+;; NOTE Install instructions
+;; brew install rust
+;; git clone https://github.com/phildawes/racer.git ~
+;; cd ~/racer
+;; cargo build --release
+;; mv ~/racer/release/racer /usr/local/bin
+;; rm -rf ~/racer
+
+(use-package rust-mode
+  :mode "\\.rs$"
+  :config
+  (build-for! rust-mode "cargo run" "Cargo.toml")
+  (use-package flycheck-rust
+    :config (add-hook! rust-mode 'flycheck-mode))
+
+  (use-package racer
+    :config
+    (bind! :m "gd" 'racer-find-definition)
+    (setq racer-cmd "/usr/local/bin/racer"
+          racer-rust-src-path "~/Dropbox/lib/rust/src/")
+
+    (add-company-backend! rust-mode (racer))
+
+    (add-hook! rust-mode
+      (racer-activate)
+      (racer-turn-on-eldoc)
+      (add-hook! flycheck-mode 'flycheck-rust-setup))))
+
+(provide 'module-rust)
+;;; module-rust.el ends here