Make sure vim-misc is installed, politely complain if it isn't

autoload/xolox/notes.vim

@@ -1,12 +1,12 @@
 " Vim auto-load script
 " Author: Peter Odding <peter@peterodding.com>
-" Last Change: July 18, 2013
+" Last Change: August 19, 2013
 " URL: http://peterodding.com/code/vim/notes/
 
 " Note: This file is encoded in UTF-8 including a byte order mark so
 " that Vim loads the script using the right encoding transparently.
 
-let g:xolox#notes#version = '0.23.1'
+let g:xolox#notes#version = '0.23.2'
 let g:xolox#notes#url_pattern = '\<\(mailto:\|javascript:\|\w\{3,}://\)\(\S*\w\)\+/\?'
 let s:scriptdir = expand('<sfile>:p:h')
 

plugin/notes.vim

@@ -1,6 +1,6 @@
 " Vim plug-in
 " Author: Peter Odding <peter@peterodding.com>
-" Last Change: June 23, 2013
+" Last Change: August 19, 2013
 " URL: http://peterodding.com/code/vim/notes/
 
 " Support for automatic update using the GLVS plug-in.
@@ -11,6 +11,19 @@ if &cp || exists('g:loaded_notes')
   finish
 endif
 
+" Make sure vim-misc is installed.
+try
+  " The point of this code is to do something completely innocent while making
+  " sure the vim-misc plug-in is installed. We specifically don't use Vim's
+  " exists() function because it doesn't load auto-load scripts that haven't
+  " already been loaded yet (last tested on Vim 7.3).
+  call type(g:xolox#misc#version)
+catch
+  echomsg "Warning: The vim-notes plug-in requires the vim-misc plug-in which seems not to be installed! For more information please review the installation instructions in the readme (also available on the homepage and on GitHub). The vim-notes plug-in will now be disabled."
+  let g:loaded_notes = 1
+  finish
+endtry
+
 " Initialize the configuration defaults.
 call xolox#notes#init()