static int ai_writeTripleFile(Collection<TripleWeb> triples, OutputStream out) ctex {

  print("Writing triple file");

  new L<S> names;

  new Map<S, Int> index;

  ai_writeTripleFile_precollectNames(names, index, triples);

  new ByteArrayOutputStream baos;

  PrintWriter writer = utf8printWriter(baos);

  int n = 0;

  for (TripleWeb w : triples) {

    ++n;

    S title = null;

    S moreInfo = quote(str(w.globalID())) + " " + quote(unnull(title)) + " " + quote(unnull(w.source())) + " " + (w.unverified() ? "u" : "v") + " " + w.created();

    O result = w.result();

    if (result != null)

      moreInfo += " (" + sfu(result) + ")";

    writer.write(

      ai_writeTripleFile_indexGet(names, index, w.a) + " " +

      ai_writeTripleFile_indexGet(names, index, w.b) + " " +

      ai_writeTripleFile_indexGet(names, index, w.c) + " " + moreInfo + "\n");

  }

  writer.flush();

  //out.println(struct(names));

  print("Have " + n2(names, "name") + ", " + toM(baos.size()) + "M buffered bytes");

  PrintWriter writer2 = utf8printWriter(out);

  for (S s : names)

    writer2.println(quoteUnlessIdentifierOrInteger(s));

  writer2.println();

  writer2.flush();

  baos.writeTo(out);

  ret n;

}

static int ai_writeTripleFile_indexGet(L<S> names, Map<S, Int> index, S s) {

  Int i = index.get(s);

  if (i == null) {

    i = l(names);

    names.add(s);

    index.put(s, i);

  }

  ret i;

}

static void ai_writeTripleFile_precollectNames(L<S> names, Map<S, Int> index, Collection<TripleWeb> triples) {

  for (TripleWeb w : triples) {

    ai_writeTripleFile_indexGet(names, index, w.a);

    ai_writeTripleFile_indexGet(names, index, w.b);

    ai_writeTripleFile_indexGet(names, index, w.c);

  }

  sortInPlaceIC(names);

  index.clear();

  for i over names: index.put(names.get(i), i);

}