这段时间在熟悉一套系统的代码，经常要查找某个变量或函数名在哪些文件中被引用到了 ，虽然在linux下面grep一下就行了，但要查看每处的上下文，还是得打开文件．还好用的是emacs，有什么不爽就自己扩展
刚用elisp时倒郁闷了一把，elisp貌视不支持尾递归（??还需查证） ，我一上来就用在scheme中惯用的过程自调用的方式来进行递归查找目录中的文件，结果很轻易就会超过elisp的最大求值嵌套深度，改为用elisp中的while则正常.
实现了search-direct和search-file二个函数，分别是查找指定目录和指定文件，查找结果会加上文件名和行号，内容在结果窗口显示，在结果行上回车则会自动打开相应文件并跳到相应行．不足还有很多，忙过这段时间再扩展了 :-) 保存下面的代码自己本地目录，再在.emacs中添加(require 'file-search) 就可以了
效果图：
file-search.el
;;; file-search.el
(defconst fs-file-search-buffer-name "*file-search*")
(defvar fs-file-list-length 0)
(defvar fs-file-search-str "")
(defvar fs-match-regexp "")
(defvar fs-file-search-keymap (make-sparse-keymap))
(define-key fs-file-search-keymap (kbd "RET") 'fs-result-choose)
(defface fs-file-name-face '((t (:foreground "red" :bold t :underline t)))
"Face used to highlight the file name")
(defface fs-line-face '((t (:foreground "green" :bold nil :underline nil)))
"Face used to highlight the line number")
;;查找列表中所有文件
(defun fs-search-list-file (list)
(while list
(let ((file-name (car list)))
(if (not (file-accessible-directory-p file-name))
(progn
(message "current file:%s %d in %d"
file-name
( + (- fs-file-list-length (length list)) 1)
fs-file-list-length)
(fs-search-file file-name 1))))
(setq list (cdr list))))
;;查找指定目录
(defun fs-search-directory (dir-name)
(if (file-accessible-directory-p dir-name)
(let ((list (cdr (cdr (directory-files dir-name t fs-match-regexp)))))
(setq fs-file-list-length (length list))
(fs-search-list-file list))
(message "%s is a invaild directory name" dir-name)))
;;查找指定文件
(defun fs-search-file (file-name point)
(let ((buf (get-buffer (file-name-nondirectory file-name)))
(bpt 0))
(with-current-buffer (find-file-noselect file-name)
(if buf
(setq bpt (point)))
(while point
(goto-char point)
(setq point (search-forward fs-file-search-str nil '(nil)))
(if point
(let ((b-pt (line-beginning-position))
(e-pt (line-end-position)))
(fs-insert-result
(count-lines 1 point)
file-name
(buffer-substring b-pt e-pt)))))
(if buf
(goto-char bpt)
(kill-buffer (current-buffer))))))
;;给出结果buffer
(defun fs-get-search-result-buffer()
(get-buffer-create fs-file-search-buffer-name))
;;插入查找结果
(defun fs-insert-result (line file text)
(with-current-buffer (fs-get-search-result-buffer)
(setq buffer-read-only nil)
(goto-char (point-max))
(let ((bpt (point)))
(insert (file-name-nondirectory file))
(set-text-properties bpt (point-max) '(face fs-file-name-face))
(put-text-property bpt (point-max) 'keymap fs-file-search-keymap)
(put-text-property bpt (point-max) 'filename file)
(put-text-property bpt (point-max) 'nline line))
(goto-char (point-max))
(let ((bpt (point)))
(insert "(" (number-to-string line) "): ")
(set-text-properties bpt (point-max) '(face fs-line-face)))
(insert text "/n")
(setq buffer-read-only t)))
;;显示结果窗口
(defun fs-show-result-window ()
(with-current-buffer (fs-get-search-result-buffer)
(let ((w (or (get-buffer-window fs-file-search-buffer-name)
(split-window-vertically -10))))
(set-window-buffer w (current-buffer))
(select-window w)
(goto-line 1))))
;;在查找结果上按回车的处理函数
(defun fs-result-choose()
(interactive)
(let ((bpt (line-beginning-position)))
(let ((line (get-text-property bpt 'nline))
(file (get-text-property bpt 'filename)))
(select-window (next-window))
(find-file file)
(goto-line line))))
;;查找目录
;;;###autoload
(defun search-directory(str dir match-regexp)
(interactive "ssearch string: /nDsearch directory: /nsmatch-regexp:")
(kill-buffer (fs-get-search-result-buffer))
(setq fs-file-search-str str)
(setq fs-match-regexp match-regexp)
(fs-search-directory dir)
(fs-show-result-window))
;;查找目录
;;;###autoload
(defun search-file(str file)
(interactive "ssearch string: /nffile:")
(kill-buffer (fs-get-search-result-buffer))
(setq fs-file-search-str str)
(fs-search-file file 1)
(fs-show-result-window))
(provide 'file-search)