見たい文字だけを表示する elisp (dnso.el)

dnso.el

;;; dnso.el -- Do not show off!

;; MAHALO License (based on MIT License)
;;
;; Copyright (c) 2012 Wataru MIYAGUNI (gonngo _at_ gmail.com)
;;
;; Permission is hereby granted, free of charge, to any person obtaining a copy
;; of this software and associated documentation files (the "Software"), to deal
;; in the Software without restriction, including without limitation the rights
;; to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
;; copies of the Software, and to permit persons to whom the Software is
;; furnished to do so, subject to the following conditions:
;;
;;   1. The above copyright notice and this permission notice shall be included in
;;      all copies or substantial portions of the Software.
;;   2. Shall be grateful for something (including, but not limited this software).
;;
;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
;; IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
;; FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
;; AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
;; LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
;; OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
;; THE SOFTWARE.

;;; Code:

;; (setq dnso:match-keywords "a-zA-Z") ;; defualt

;;; Demo:

;; http://youtu.be/MZaWMpJPN7s

(defconst dnso:match-keywords "a-zA-Z")

(defface dnso:face
  '((t (:foreground "Black" :background "Black")))
  "Only Only Only face")

(defvar dnso:overlays nil)

(defconst dnso:buffer "*Only Only Buffer*")

(defun dnso:keywords-point (sp regexp)
  (save-excursion
    (goto-char sp)
    (let (p)
      (setq p (re-search-forward regexp nil t))
      (if (integerp p) (1- p) p))))

(defun dnso:match-keywords-point (sp)
  (dnso:keywords-point sp (concat "[" dnso:match-keywords "]")))

(defun dnso:no-match-keywords-point (sp)
  (dnso:keywords-point sp (concat "[^" dnso:match-keywords "]")))

(defun dnso:show ()
  (interactive)
  (save-excursion
    (copy-to-buffer (get-buffer-create dnso:buffer) (point-min) (point-max))
    (let ((buffer (current-buffer))
          face)
      (with-current-buffer dnso:buffer
        (switch-to-buffer (current-buffer))
        (goto-char (point-min))
        (insert " ")
        (goto-char (point-min))
        (setq dnso:overlays nil)

        (set-face-background 'dnso:face (background-color-at-point))
        (set-face-foreground 'dnso:face (background-color-at-point))

        (catch 'loop
          (let (overlay p1 p2)
            (while t
              (setq p1 (dnso:no-match-keywords-point (point)))
              (when (null p1) (throw 'loop nil))
              (setq p2 (dnso:match-keywords-point p1))
              (when (null p2) (setq p2 (point-max)))
              (setq overlay (make-overlay p1 p2))
              (overlay-put overlay 'face 'dnso:face)
              (setq dnso:overlays (cons overlay dnso:overlays))
              (goto-char p2)
              )))

        (goto-char (point-min))
        (delete-char 1)
        (view-mode)))))