simple useful functions

[Tak Ota]

If you think the following two functions are universally useful please
consider incorporating them in simple.el or any appropriate package.
If not disregard.

-Tak

(defun collect-string (regexp &optional num)
  "Collect strings of REGEXP (or optional NUM paren) from the
current buffer into a collection buffer."
  (interactive "sCollect string (regexp): \nP")
  (let ((collection-buffer
         (get-buffer-create (format "*Collection of \"%s\" *" regexp))))
    (with-current-buffer collection-buffer (erase-buffer))
    (save-excursion
      (goto-char (point-min))
      (while (re-search-forward regexp nil t)
        (let ((str (match-string (or num 0))))
          (if str
              (with-current-buffer collection-buffer
                (insert str)
                (or (zerop (current-column))
                    (insert "\n")))))))
    (pop-to-buffer collection-buffer)
    (goto-char (point-min))))

(defun source (script &optional shell keep-current-directory)
  "Source the specified shell script.
Source the shell SCRIPT and import the environment into this
emacs.  The optional SHELL specifies the shell other than the
default `shell-file-name'.  When KEEP-CURRENT-DIRECTORY is nil,
which is the default, the current directory is temporarily
changed to the directory where the script resides while sourcing
the script."
  (interactive "fscript file: ")
  (if (null shell)
      (setq shell shell-file-name))
  (with-temp-buffer
    (unless keep-current-directory
      (setq default-directory (file-name-directory script)))
    (call-process shell nil t nil "-c" (concat "source " script "; printenv"))
    (while (re-search-backward "^\\([^=]+\\)=\\(.*\\)$" nil t)
      (setenv (match-string 1) (match-string 2)))))