Add Michael Fogleman's Emacs macro

editions/tw5.com/tiddlers/tips/Editing Tiddlers with Emacs.tid

@@ -0,0 +1,26 @@
+created: 20140406210404245
+modified: 20140406210649764
+tags: tips
+title: Editing Tiddlers with Emacs
+type: text/vnd.tiddlywiki
+
+This [[Emacs|http://www.gnu.org/software/emacs/]] macro from Michael Fogleman simplifies editing tiddlers in `*.tid` files by automatically updating the `modified` field:
+
+```
+(defun tid-time ()
+  "If called in a tiddler file, this function updates the metadata to
+  reflect the modification time."
+  (interactive)
+  (when
+      (and
+       (> (length (buffer-file-name)) 4)
+       (string-equal (substring (buffer-file-name) -4) ".tid"))
+      (save-excursion
+        (goto-char (point-min))
+
+        (search-forward "modified: ")
+        (beginning-of-line)
+
+        (kill-line)
+        (insert (format-time-string "modified: %Y%m%d%H%M%S%3N")))))
+```