Is it possible to index a plain text file (a book) in vim such as :
1. This line contains the words : London, Berlin, Paris
2. In this line, I write about :
I took the liberty of writing the following function, based on using the :g/STRING/#
command to get the matches. I read the results of this command into a list, and then process it to return a list of matching line numbers:
function! IndexByWord( this_word )
redir => result
sil! exe ':g/' . a:this_word . '/#'
redir END
let tmp_list = split(strtrans(result),"\\^\@ *")
let res_list = []
call map(tmp_list, 'add(res_list,matchstr(v:val,"^[0-9]*"))')
let res = a:this_word . ' : ' . string(res_list)
let res = substitute(res, "[\\[\\]\\']", "", "g")
echo res
endfunction
So you could call this function on all the words you wish (or write a script to do so) and direct the output to a file. Not very elegant, perhaps, but nicely self-contained.
Hope this helps, rather than hinders.