A vim operator function to search for a word with a motion

ag-operator.vim

nnoremap <leader>g :set operatorfunc=AgOperator<cr>g@
vnoremap <leader>g :<c-u>call AgOperator(visualmode())<cr>

function! AgOperator(type)
  if a:type ==# 'v'
      normal! `<v`>y
  elseif a:type ==# 'char'
      normal! `[v`]y
  else
      return
  endif

  silent execute "Ag " . shellescape(@@) . " ."
  copen
endfunction