include_c "string.h";
use "sequence_queries.g";
use "iterator_models.g";

fun main() -> int@ {
  let seq = "hello world";
  let seq_end = seq + strlen(seq);
  let subseq = "lo";
  let subseq_end = subseq + strlen(subseq);

  let i = find_subsequence(seq, seq_end, subseq, subseq_end);
  if (not equal(subseq, subseq_end, i))
    return -1;

  let i = find_subsequence(seq, seq_end, subseq, subseq_end,
			   fun (char a, char b): a == b);
  if (not equal(subseq, subseq_end, i, fun (char a, char b): a == b))
    return -1;

  return 0;
}