Highlighting() breaks quickfix

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Hi,

I like and use Highlighting() from
http://vim.wikia.com/wiki/Highlight_all_search_pattern_matches

" Smart <Enter> for highlighting
let g:highlighting = 0
function! Highlighting()
if g:highlighting == 1 && @/ =~ '^\\<'.expand('<cword>').'\\>$'
let g:highlighting = 0
return ":silent nohlsearch\<CR>"
endif
let @/ = '\<'.expand('<cword>').'\>'
let g:highlighting = 1
return ":silent set hlsearch\<CR>"
endfunction
"nnoremap <silent> <expr> <CR> Highlighting()

" remove highlighting
:nnoremap <silent> <Space> :nohlsearch<Bar>:echo<CR>

Unfortunately, it breaks quickfix; after pressing <CR> in the quickfix
window, nothing happens.

I have tried to counter this problem by adding

if &buftype == "quickfix"
return 'execute "normal! <CR>"'
endif

to the start of the function, but then I get an error message
complaining that the quickfix window is not modifiable. So, I guess

normal! <CR>

is not the proper thing to say in the quickfix window. What is? How can
I make this function not break quickfix?

Thank you for any suggestions,

Matěj Cepl
--
http://www.ceplovi.cz/matej/, Jabber: mcepl@ceplovi.cz
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