Combine the power of [I and :ilist /pattern/ in Vim

gistfile1.vim

function! IList()
  let term = input("IList: /")
  if term == ''
    let term = expand('<cword>')
  endif
  let v:errmsg = ''
  redir =>slist
    exe 'ilist /' . term
  redir END
  if v:errmsg == ''
    let llist = split(slist, "\n")   " remove \@ nuls
    let slist = join(llist, "\n")
    call filter(llist, 'v:val =~ "^\\s\\+\\d\\+:"')
    let choice = str2nr(input('Find: '))
    call histdel('input', -1)  " remove numeric choice leaving named term as last
    if (choice > 0) && (choice <= len(llist))
      let line = matchstr(llist[choice-1], '^\s*\d\+:\s\+\zs\d\+')
      let file = split(matchstr(slist, '\_.*\%(\_^\|\n\)\zs\S\+\ze\_.\{-}\n\s\+' . choice))[0]   " remove \@ nul
      if bufexists(file)
        exe 'buffer ' . file
      else
        exe 'edit ' . file
      endif
      exe line
      normal! 0
      call search(term, 'c')
    endif
  else
    let v:errmsg .= ': ' . term
  endif
endfunction

nnoremap [I :call IList()<cr>