Emacs: auto-complete-clang-async package

1. Install clang-complete and auto-complete-clang.el
2. ${HOME}/.emacs
3. Original include headers
4. Execution result

1 Install clang-complete and auto-complete-clang.el

Install packages for building clang-complete. And build clang-complete.

This article will load .elisp directory as emacs lisp directory in ${HOME}/.emacs with as below. Please change your emacs lisp directory.

;; emacs lisp directory path(setq load-path (append (list (expand-file-name “~/.elisp/”) ) load-path))

1.1 Ubuntu 16.04

Install llvm-dev and libclang-dev.

$ sudo apt-get install -y clang llvm-dev libclang-dev$ git clone cd emacs-clang-complete-async$ make$ cp clang-complete ~/bin/$ cp auto-complete-clang.el ~/.elisp/

1.2 CentOS 7

Install llvm-devel, clang-devel and zlib.

$ sudo yum install -y llvm-devel clang-devel zlib$ git clone cd emacs-clang-complete-async$ make$ cp clang-complete ~/bin/$ cp auto-complete-clang.el ~/.elisp/

1.3 OSX

Because XCode does not have enought Clang header files, install clang and llvm with Homebrew.

$ brew install –with-clang –all-targets –rtti –universal –jit llvm$ git clone cd emacs-clang-complete-async$ make LLVM_CONFIG=/usr/local/opt/llvm/bin/llvm-config CC=/usr/local/opt/llvm/bin/clang$ cp clang-complete ~/bin/$ cp auto-complete-clang.el ~/.elisp/

2 ${HOME}/.emacs

Load auto-complete-clang-async and add to c++mode-hook in ${HOME}/.emacs.

(require ‘auto-complete-clang-async)(add-hook ‘c++-mode-hook ‘(lambda() (setq ac-clang-complete-executable “~/bin/clang-complete”) (setq ac-sources ‘(ac-source-clang-async)) (ac-clang-launch-completion-process)))

This settings provides auto complete of standard include headers.

3 Original include headers

Auto complete of original include headers needs setting ac-clang-cflags or calling ac-clang-set-cflagas.

3.1 Set ac-clang-cflags in ${HOME}/.emacs

Setting ac-clang-cflags in ${HOME}/.emacs.

(custom-set-variables ‘(ac-clang-cflags ‘(“-I/path/to/include”)))

3.2 Call ac-clang-set-cflags in M-x

Call ac-clang-set-cflags in M-x.

M-x ac-clang-set-cflagsNew cflags: -I/path/to/include

3.3 Add custom elisp initial file to each source tree (Recommend)

The .dir-locals cannot set ac-clang-cflags properly (.dir-locals cannot change custom-set-variables and ac-clang-cflags is custom-set-variables).

The great answer is in StackExchange.

Adding the following setting to ${HOME}/.emacs which can set original value for source tree if source tree has a .settings.el.

(defun recursive-load-dir-settings (currentfile) (let ((lds-dir (locate-dominating-file currentfile “.settings.el”))) (when lds-dir (progn (load-file (concat lds-dir “.settings.el”)) (recursive-load-dir-settings (file-truename(concat lds-dir “..”)))))))(defun load-dir-settings() (interactive) (when buffer-file-name (recursive-load-dir-settings buffer-file-name)))(add-hook ‘find-file-hook ‘load-dir-settings)

Adding the following .settings.el in source tree. You can multiple original includes to list.

(when (equal major-mode ‘c++-mode) (setq ac-clang-cflags (list (concat “-I” (expand-file-name (concat lds-dir “path/to/include”))))) (ac-clang-update-cmdlineargs) (print ac-clang-cflags))

4 Execution result

This article uses the following source tree.

$ tree ..|– include| `– myclass.h`– src `– main.cc2 directories, 2 files

Add .settings.el which adds include directory to ac-clang-cflags.

$ cat .settings.el(when (equal major-mode ‘c++-mode) (setq ac-clang-cflags (list (concat “-I” (expand-file-name (concat lds-dir “include”))))) (ac-clang-update-cmdlineargs) (print ac-clang-cflags))

myclass.h defines myclass which has getValue method.

$ cat include/myclass.h#ifndef __MYCLASS_H#define __MYCLASS_Hclass myclass { private: int mValue; public: myclass(int value) : mValue(value) {} int getValue() { return mValue; }}#endif /** __MY_CLASS_H */

The myclass can be auto completed.

iostream can be auto completed.

Table of Contents