Export: Better handling of colon examples.

Lines preceded by a colon are treated as fixed-width examples.
This commit improves the moment when the protection of these lines
happens during preprocessing.  And it enforces that a space must
follow the colon for the line to be treated in this way.

ORGWEBPAGE/Changes.org

@@ -15,6 +15,17 @@
   :VISIBILITY: content
   :END:
 
+
+** Incompatible changes
+
+*** Short examples must have a space after the colon
+
+    Short literal examples can be created by preceeding lines
+    with a colon.  Such lines must now have a space after the
+    colon.  I believe this is already general practice, but now
+    it must be like this.  The only exception are lines what are
+    empty except for the colon.    
+
 ** Details
 
 *** The relative timer can be paused

doc/ChangeLog

@@ -1,3 +1,8 @@
+2009-01-09  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* org.texi (Literal examples): Document that a space must follow
+	the colon in short examples.
+
 2009-01-08  Carsten Dominik  <carsten.dominik@gmail.com>
 
 	* org.texi (Relative timer): Document `org-timer-stop'.

doc/org.texi

@@ -7376,10 +7376,12 @@ Some example from a text file.
 @end example
 
 For simplicity when using small examples, you can also start the example
-lines with a colon:
+lines with a colon followed by a space.  There may also be additional
+whitespace before the colon:
 
 @example
-: Some example from a text file.
+Here is an example
+   : Some example from a text file.
 @end example
 
 @cindex formatting source code, markup rules

lisp/ChangeLog

@@ -1,3 +1,18 @@
+2009-01-09  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* org-export-latex.el (org-export-latex-fixed-width): Enforce the
+	space after the colon in short examples.
+
+	* org-exp.el (org-export-protect-colon-examples): Rewritten, to
+	enforce a space after the colon.  However, we also allow lines
+	that are *only* a colon.
+	(org-export-as-html): Enforce the space after the colon in short
+	examples.
+	(org-export-preprocess-string): Do the colon example protection
+	earlier.
+	(org-export-remove-timestamps): Do not check for protection at the
+	end of the line.
+
 2009-01-08  Carsten Dominik  <carsten.dominik@gmail.com>
 
 	* org.el (org-format-latex-options): Add new matcher for single

lisp/org-exp.el

@@ -1527,6 +1527,9 @@ on this string to produce the exported version."
       ;; Handle source code snippets
       (org-export-replace-src-segments-and-examples backend)
 
+      ;; Protect short examples marked by a leading colon
+      (org-export-protect-colon-examples)
+
       ;; Normalize footnotes
       (when (plist-get parameters :footnotes)
 	(org-footnote-normalize nil t))
@@ -1552,19 +1555,12 @@ on this string to produce the exported version."
       ;; Remove todo-keywords before exporting, if the user has requested so
       (org-export-remove-headline-metadata parameters)
 
-      ;; Remove timestamps, if the user has requested so
-      (org-export-remove-clock-lines)
-      (unless (plist-get parameters :timestamps)
-	(org-export-remove-timestamps))
-
       ;; Find targets in comments and move them out of comments,
       ;; but mark them as targets that should be invisible
       (setq target-alist (org-export-handle-invisible-targets target-alist))
 
-      ;; Protect short examples
-      (org-export-protect-colon-examples)
-
-      ;; Protect backend specific stuff, throw away the others.
+      ;; Select and protect backend specific stuff, throw away stuff
+      ;; that is specific for other backends
       (org-export-select-backend-specific-text backend)
 
       ;; Protect quoted subtrees
@@ -1576,6 +1572,11 @@ on this string to produce the exported version."
       ;; Blockquotes and verse
       (org-export-mark-blockquote-and-verse)
 
+      ;; Remove timestamps, if the user has requested so
+      (org-export-remove-clock-lines)
+      (unless (plist-get parameters :timestamps)
+	(org-export-remove-timestamps))
+
       ;; Attach captions to the correct object
       (setq target-alist (org-export-attach-captions-and-attributes
 			  backend target-alist))
@@ -1606,16 +1607,16 @@ on this string to produce the exported version."
       ;; Another hook
       (run-hooks 'org-export-preprocess-before-backend-specifics-hook)
 
-      ;; Specific LaTeX stuff
+      ;; LaTeX-specific preprocessing
       (when latexp
 	(require 'org-export-latex nil)
 	(org-export-latex-preprocess))
 
-      ;; Specific ASCII stuff
+      ;; ASCII-specific preprocessing
       (when asciip
 	(org-export-ascii-preprocess))
 
-      ;; Specific HTML stuff
+      ;; HTML-specific preprocessing
       (when htmlp
 	(org-export-html-preprocess parameters))
 
@@ -1887,9 +1888,15 @@ from the buffer."
 (defun org-export-protect-colon-examples ()
   "Protect lines starting with a colon."
   (goto-char (point-min))
-  (while (re-search-forward "^[ \t]*:.*\\(\n[ \t]*:.*\\)*" nil t)
-    (add-text-properties (match-beginning 0) (match-end 0)
-			 '(org-protected t))))
+  (let ((re "^[ \t]*:\\([ \t]\\|$\\)") beg end)
+    (while (re-search-forward re nil t)
+      (beginning-of-line 1)
+      (setq beg (point))
+      (while (looking-at re)
+	(end-of-line 1)
+	(or (eobp) (forward-char 1)))
+      (add-text-properties beg (if (bolp) (1- (point)) (point))
+			   '(org-protected t)))))
 
 (defun org-export-select-backend-specific-text (backend)
   (let ((formatters
@@ -3440,7 +3447,7 @@ lang=\"%s\" xml:lang=\"%s\">
 
 	  ;; Fixed-width, verbatim lines (examples)
 	  (when (and org-export-with-fixed-width
-		     (string-match "^[ \t]*:\\(.*\\)" line))
+		     (string-match "^[ \t]*:\\(\\([ \t]\\|$\\).*\\)" line))
 	    (when (not infixed)
 	      (setq infixed t)
 	      (org-close-par-maybe)

lisp/org-export-latex.el

@@ -1022,17 +1022,17 @@ The conversion is made depending of STRING-BEFORE and STRING-AFTER."
 (defun org-export-latex-fixed-width (opt)
   "When OPT is non-nil convert fixed-width sections to LaTeX."
   (goto-char (point-min))
-  (while (re-search-forward "^[ \t]*:" nil t)
+  (while (re-search-forward "^[ \t]*:\\([ \t]\\|$\\)" nil t)
     (if opt
 	(progn (goto-char (match-beginning 0))
 	       (insert "\\begin{verbatim}\n")
-	       (while (looking-at "^\\([ \t]*\\):\\(.*\\)$")
+	       (while (looking-at "^\\([ \t]*\\):\\(\\([ \t]\\|$\\).*\\)$")
 		 (replace-match (concat (match-string 1)
 					(match-string 2)) t t)
 		 (forward-line))
 	       (insert "\\end{verbatim}\n\n"))
       (progn (goto-char (match-beginning 0))
-	     (while (looking-at "^\\([ \t]*\\):\\(.*\\)$")
+	     (while (looking-at "^\\([ \t]*\\):\\(\\([ \t]\\|$\\).*\\)$")
 	       (replace-match (concat "%" (match-string 1)
 				      (match-string 2)) t t)
 	       (forward-line))))))