HighLight Current Line in GVim 7

augroup vim7highlightCurrentLineInActiveWindow
  au WinEnter * if g:HighlightCurrentLine | setlocal cul | endif
  au WinLeave * if g:HighlightCurrentLine | setlocal nocul | endif
augroup end
function! s:ToggleHighlightCurrentLine()
  if !exists('g:HighlightCurrentLine') || g:HighlightCurrentLine==0
    setlocal cul
    let g:HighlightCurrentLine=1
  else
    setlocal nocul
    let g:HighlightCurrentLine=0
  endif
endfunction
command! ToggleHighlightCurrentLine :call ToggleHighlightCurrentLine()
call ToggleHighlightCurrentLine()

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