開(kāi)發(fā)速記-emacs篇: haskell+nix開(kāi)發(fā)模式

安裝nix并配置channel:

sudo install -d -m755 -o $(id -u) -g $(id -g) /nix
curl https://nixos.org/nix/install | sh

nix-channel --add https://nixos.org/channels/nixos-20.03 nixos-20.03
nix-channel --update nixos-20.03

安裝cachix 并配置iohk緩存

nix-env -f ~/.nix-defexpr/channels/nixos-20.03 -iA cachix
cachix use iohk

安裝cabal

nix-env -f ~/.nix-defexpr/channels/nixos-20.03 -iA cabal-install

安裝emacs

nix-env -f ~/.nix-defexpr/channels/nixos-20.03 -iA emacs

配置emacs:

創(chuàng)建并拷貝github文件內(nèi)容至~/.emacs.d/init.el
https://github.com/clojurians-org/my-emacs/blob/master/init.el
相關(guān)代碼片斷講解

安裝dante-mode

(dolist (package '(paredit restclient json-mode typescript-mode
                   dap-mode lsp-java gradle-mode
                   dante cider
                   ))
  (unless (package-installed-p package)
    (package-install package)))

配置dante-mode

(use-package dante
  :ensure t
  :after haskell-mode
  :commands 'dante-mode
  :init
  (add-hook 'haskell-mode-hook 'flycheck-mode)
  (add-hook 'haskell-mode-hook 'dante-mode)
  )

創(chuàng)建cabal項(xiàng)目:

mkdir my-app && cd my-app 
cabal init --libandexe --source-dir=src --application-dir=app
cabal new-configure

添加stack版本支持(僅創(chuàng)建文件即可)

larrys-MacBook-Pro:my-app larluo$ cat stack.yaml 
resolver: lts-14.27
packages:
- .

添加依賴

larrys-MacBook-Pro:my-app larluo$ cat my-app.cabal
cabal-version:       >=1.10
-- Initial package description 'my-app.cabal' generated by 'cabal init'.
-- For further documentation, see http://haskell.org/cabal/users-guide/

name:                my-app
version:             0.1.0.0
-- synopsis:
-- description:
-- bug-reports:
-- license:
license-file:        LICENSE
author:              clojurians-org
maintainer:          larluo@clojurians.org
-- copyright:
-- category:
build-type:          Simple
extra-source-files:  CHANGELOG.md

library
  exposed-modules:     MyLib
  -- other-modules:
  -- other-extensions:
  build-depends:       
      base
    , bytestring
    , cryptonite
                      
  hs-source-dirs:      src
  default-language:    Haskell2010

executable my-app
  main-is:             Main.hs
  -- other-modules:
  -- other-extensions:
  build-depends:       base, my-app
  hs-source-dirs:      app
  default-language:    Haskell2010

切換至nix集成模式

[ haskell.nix: https://github.com/input-output-hk/haskell.nix ]

如使用iohk緩存川梅，請(qǐng)參考 https://github.com/input-output-hk/haskell.nix/blob/master/ci.nix中的nixpkgs版本，替換~/.nix-defexpr/channels/nixos-20.03

larrys-MacBook-Pro:my-app larluo$ cat default.nix
{ pkgs ? import ~/.nix-defexpr/channels/nixos-20.03 (import (builtins.fetchTarball https://github.com/input-output-hk/haskell.nix/archive/master.tar.gz))
}:
  pkgs.haskell-nix.stackProject {
    src = pkgs.haskell-nix.haskellLib.cleanGit { src = ./.; };
  }

進(jìn)入nix-shell開(kāi)發(fā)環(huán)境

nix-shell -A shellFor

分別為library及application添加emacs配置

[nix-shell:~/my-tmp/my-app]$ cat src/.dir-locals.el 
((nil . (
  (dante-methods . (new-build))
  (dante-target . "lib:my-app")
                  )))

[nix-shell:~/my-tmp/my-app]$ cat app/.dir-locals.el 
((nil . (
  (dante-methods . (new-build))
  (dante-target . "exe:my-app")
                  )))

使用emacs 編碼

emacs -nw src/MyLib.hs

使用[C-c, !, l] 打開(kāi)flycheck顯示錯(cuò)誤提示

image.png

使用[C-c, "]運(yùn)行代碼得到結(jié)果