title: option omnifunc is not set in vim?
body: <pre><code>root@debian:/home/debian# echo  $PYTHONPATH
  /usr/lib/python2.7/:
  
  root@debian:/home/debian# ls /usr/share/vim/vim73/autoload/ 
  adacomplete.vim  decada.vim htmlcomplete.vim    netrw.vim        pythoncomplete.vim  spellfile.vim       tohtml.vim       zip.vim
  ada.vim      getscript.vim  javascriptcomplete.vim  paste.vim        rcomplete.vim   sqlcomplete.vim     vimball.vim
  ccomplete.vim    gnat.vim   netrwFileHandlers.vim   phpcomplete.vim      README.txt      syntaxcomplete.vim  xml
  csscomplete.vim  gzip.vim   netrwSettings.vim   python3complete.vim  rubycomplete.vim    tar.vim         xmlcomplete.vim
  
  cat  /etc/vim/vimrc
  runtime! debian.vim
  set mouse=a     " Enable mouse usage (all modes)
  set ts=4
  set expandtab 
  set shiftwidth=4 
  if filereadable("/etc/vim/vimrc.local")
    source /etc/vim/vimrc.local
  endif
  set number
  set textwidth=80
  syntax enable 
  filetype indent on
  filetype plugin indent on
  autocmd FileType python setlocal et sta sw=4 sts=4
  autocmd FileType python set omnifunc=pythoncomplete#Complete
  autocmd FileType javascript set omnifunc=javascriptcomplete#CompleteJS
  autocmd FileType html set omnifunc=htmlcomplete#CompleteTags
  autocmd FileType css set omnifunc=csscomplete#CompleteCSS
  autocmd FileType xml set omnifunc=xmlcomplete#CompleteTags
  autocmd FileType java set omnifunc=javacomplete#Complete
  if has("autocmd") &amp;&amp; exists("+omnifunc")
       autocmd Filetype *
     \ if &amp;omnifunc == "" |
     \   setlocal omnifunc=syntaxcomplete#Complete |
     \ endif
  endif
  </code></pre>
  
  <p>when i edit a python file such as the attatchment ,input <code>ctrl+x</code> ,output is
  attachment1:
  <img src="https://i.stack.imgur.com/dJLDf.png" alt="enter image description here"></p>
  
  <p>input <code>ctrl+o</code> :
  <img src="https://i.stack.imgur.com/RkNbZ.png" alt="enter image description here"></p>
  
  <p>option omnifunc is not set ?which setup is wrong in
  my vimrc or else where?</p>