let unlink_index = fun index ->
let (indexes, to_be_removed) =
List.partition (fun idx -> idx.idx_name <> index.idx_name)
index.idx_db.db_indexes
in
index.idx_db.db_indexes <- indexes;
match to_be_removed with
| [idx] -> idx.idx_db <- (Obj.magic 0)
| _ -> Dbf_misc.ie ()