lisp/org-macro.el

   1 ;;; org-macro.el --- Macro Replacement Code for Org Mode
   2
   3 ;; Copyright (C) 2013-2014 Free Software Foundation, Inc.
   4
   5 ;; Author: Nicolas Goaziou <n.goaziou@gmail.com>
   6 ;; Keywords: outlines, hypermedia, calendar, wp
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;; Macros are expanded with `org-macro-replace-all', which relies
  26 ;; internally on `org-macro-expand'.
  27
  28 ;; Default templates for expansion are stored in the buffer-local
  29 ;; variable `org-macro-templates'.  This variable is updated by
  30 ;; `org-macro-initialize-templates', which recursively calls
  31 ;; `org-macro--collect-macros' in order to read setup files.
  32
  33 ;; Along with macros defined through #+MACRO: keyword, default
  34 ;; templates include the following hard-coded macros:
  35 ;; {{{time(format-string)}}}, {{{property(node-property)}}},
  36 ;; {{{input-file}}} and {{{modification-time(format-string)}}}.
  37
  38 ;; Upon exporting, "ox.el" will also provide {{{author}}}, {{{date}}},
  39 ;; {{{email}}} and {{{title}}} macros.
  40
  41 ;;; Code:
  42 (require 'org-macs)
  43
  44 (declare-function org-element-at-point "org-element" ())
  45 (declare-function org-element-context "org-element" (&optional element))
  46 (declare-function org-element-property "org-element" (property element))
  47 (declare-function org-element-type "org-element" (element))
  48 (declare-function org-remove-double-quotes "org" (s))
  49 (declare-function org-mode "org" ())
  50 (declare-function org-file-contents "org" (file &optional noerror))
  51 (declare-function org-with-wide-buffer "org-macs" (&rest body))
  52
  53 ;;; Variables
  54
  55 (defvar org-macro-templates nil
  56   "Alist containing all macro templates in current buffer.
  57 Associations are in the shape of (NAME . TEMPLATE) where NAME
  58 stands for macro's name and template for its replacement value,
  59 both as strings.  This is an internal variable.  Do not set it
  60 directly, use instead:
  61
  62   #+MACRO: name template")
  63 (make-variable-buffer-local 'org-macro-templates)
  64
  65
  66 ;;; Functions
  67
  68 (defun org-macro--collect-macros ()
  69   "Collect macro definitions in current buffer and setup files.
  70 Return an alist containing all macro templates found."
  71   (let* (collect-macros                 ; For byte-compiler.
  72          (collect-macros
  73           (lambda (files templates)
  74             ;; Return an alist of macro templates.  FILES is a list of
  75             ;; setup files names read so far, used to avoid circular
  76             ;; dependencies.  TEMPLATES is the alist collected so far.
  77             (let ((case-fold-search t))
  78               (org-with-wide-buffer
  79                (goto-char (point-min))
  80                (while (re-search-forward
  81                        "^[ \t]*#\\+\\(MACRO\\|SETUPFILE\\):" nil t)
  82                  (let ((element (org-element-at-point)))
  83                    (when (eq (org-element-type element) 'keyword)
  84                      (let ((val (org-element-property :value element)))
  85                        (if (equal (org-element-property :key element) "MACRO")
  86                            ;; Install macro in TEMPLATES.
  87                            (when (string-match
  88                                   "^\\(.*?\\)\\(?:\\s-+\\(.*\\)\\)?\\s-*$" val)
  89                              (let* ((name (match-string 1 val))
  90                                     (template (or (match-string 2 val) ""))
  91                                     (old-cell (assoc name templates)))
  92                                (if old-cell (setcdr old-cell template)
  93                                  (push (cons name template) templates))))
  94                          ;; Enter setup file.
  95                          (let ((file (expand-file-name
  96                                       (org-remove-double-quotes val))))
  97                            (unless (member file files)
  98                              (with-temp-buffer
  99                                (org-mode)
 100                                (insert (org-file-contents file 'noerror))
 101                                (setq templates
 102                                      (funcall collect-macros (cons file files)
 103                                               templates)))))))))))
 104               templates))))
 105     (funcall collect-macros nil nil)))
 106
 107 (defun org-macro-initialize-templates ()
 108   "Collect macro templates defined in current buffer.
 109 Templates are stored in buffer-local variable
 110 `org-macro-templates'.  In addition to buffer-defined macros, the
 111 function installs the following ones: \"property\",
 112 \"time\". and, if the buffer is associated to a file,
 113 \"input-file\" and \"modification-time\"."
 114   (let* ((templates (org-macro--collect-macros))
 115          (update-templates
 116           (lambda (cell)
 117             (let ((old-template (assoc (car cell) templates)))
 118               (if old-template (setcdr old-template (cdr cell))
 119                 (push cell templates))))))
 120     ;; Install hard-coded macros.
 121     (mapc (lambda (cell) (funcall update-templates cell))
 122           (list (cons "property" "(eval (org-entry-get nil \"$1\" 'selective))")
 123                 (cons "time" "(eval (format-time-string \"$1\"))")))
 124     (let ((visited-file (buffer-file-name (buffer-base-buffer))))
 125       (when (and visited-file (file-exists-p visited-file))
 126         (mapc (lambda (cell) (funcall update-templates cell))
 127               (list (cons "input-file" (file-name-nondirectory visited-file))
 128                     (cons "modification-time"
 129                           (format "(eval (format-time-string \"$1\" '%s))"
 130                                   (prin1-to-string
 131                                    (nth 5 (file-attributes visited-file)))))))))
 132     (setq org-macro-templates templates)))
 133
 134 (defun org-macro-expand (macro templates)
 135   "Return expanded MACRO, as a string.
 136 MACRO is an object, obtained, for example, with
 137 `org-element-context'.  TEMPLATES is an alist of templates used
 138 for expansion.  See `org-macro-templates' for a buffer-local
 139 default value.  Return nil if no template was found."
 140   (let ((template
 141          ;; Macro names are case-insensitive.
 142          (cdr (assoc-string (org-element-property :key macro) templates t))))
 143     (when template
 144       (let ((value (replace-regexp-in-string
 145                     "\\$[0-9]+"
 146                     (lambda (arg)
 147                       (or (nth (1- (string-to-number (substring arg 1)))
 148                                (org-element-property :args macro))
 149                           ;; No argument: remove place-holder.
 150                           ""))
 151                     template nil 'literal)))
 152         ;; VALUE starts with "(eval": it is a s-exp, `eval' it.
 153         (when (string-match "\\`(eval\\>" value)
 154           (setq value (eval (read value))))
 155         ;; Return string.
 156         (format "%s" (or value ""))))))
 157
 158 (defun org-macro-replace-all (templates)
 159   "Replace all macros in current buffer by their expansion.
 160 TEMPLATES is an alist of templates used for expansion.  See
 161 `org-macro-templates' for a buffer-local default value."
 162   (save-excursion
 163     (goto-char (point-min))
 164     (let (record)
 165       (while (re-search-forward "{{{[-A-Za-z0-9_]" nil t)
 166         (let ((object (org-element-context)))
 167           (when (eq (org-element-type object) 'macro)
 168             (let* ((value (org-macro-expand object templates))
 169                    (begin (org-element-property :begin object))
 170                    (signature (list begin
 171                                     object
 172                                     (org-element-property :args object))))
 173               ;; Avoid circular dependencies by checking if the same
 174               ;; macro with the same arguments is expanded at the same
 175               ;; position twice.
 176               (if (member signature record)
 177                   (error "Circular macro expansion: %s"
 178                          (org-element-property :key object))
 179                 (when value
 180                   (push signature record)
 181                   (delete-region
 182                    begin
 183                    ;; Preserve white spaces after the macro.
 184                    (progn (goto-char (org-element-property :end object))
 185                           (skip-chars-backward " \t")
 186                           (point)))
 187                   ;; Leave point before replacement in case of recursive
 188                   ;; expansions.
 189                   (save-excursion (insert value)))))))))))
 190
 191
 192 (provide 'org-macro)
 193 ;;; org-macro.el ends here