--- a/emacs.rst	Tue Jan 06 21:20:15 2015 +0200
+++ b/emacs.rst	Tue Jan 06 21:23:43 2015 +0200
@@ -31,8 +31,11 @@
   http://emacsformacosx.com/
                 Clean GNU Emacs for Mac OS X.
 
+Development.
+============
+
 Variables.
-==========
+----------
 
 Select one of::
 
@@ -40,11 +43,21 @@
   (setq variable value)
   (defvar variable value "documentation")
 
-or (replace <colon> with::
+or file local::
+
+  # Local variables:
+  # variable: value
+  # End:
 
-  # Local variables<colon>
-  # variable<colon> value
-  # End<colon>
+Find variable/function/feature by name or value.
+------------------------------------------------
+::
+
+  (apropos-value "PATT")
+  (apropos-variable "PATT")
+  (apropos-function "PATT")
+  (apropos-library "PATT")
+  (apropos-documentation "PATT")
 
 Debugging.
 ==========
@@ -63,10 +76,13 @@
 
 See value of variable ``load-history`` (by C-h v load-history RET)::
 
-  (symbol-file 'c-mode)
-  (find-lisp-object-file-name 'c-mode (symbol-function 'c-mode))
+  (symbol-file 'scheme 'provide)        ; Who provide feature.
+  (symbol-file 'nxml-mode-hook 'defvar) ; Where variable defined.
+  (symbol-file 'message-send 'defun)    ; Where function defined.
+  (symbol-file 'scheme)  ; Look for symbol despite its type.
   load-history
   (locate-library "gnus.el")
+  (find-lisp-object-file-name 'c-mode (symbol-function 'c-mode))
 
 Using edebug.
 -------------