#include <bson/bson.h>

       MongoDB, Inc

       2009-present, MongoDB, Inc.

1.30.4                                            Jun 08, 2025                                    BSON_ITER_T(3)

bson_iter_t  is  a  structure used to iterate through the elements of a bson_t. It is meant to be used on
       the stack and can be discarded at any time as it contains no external allocation.  The  contents  of  the
       structure  should  be considered private and may change between releases, however the structure size will
       not change.

       The bson_tMUST be valid for the lifetime of the iter and it is an error to modify the bson_t while using
       the iter.

          bson_iter_t iter;

          if (bson_iter_init (&iter, my_bson_doc)) {
             while (bson_iter_next (&iter)) {
                printf ("Found a field named: %s\n", bson_iter_key (&iter));
             }
          }

          bson_iter_t iter;

          if (bson_iter_init (&iter, my_bson_doc) && bson_iter_find (&iter, "my_field")) {
             printf ("Found the field named: %s\n", bson_iter_key (&iter));
          }

          bson_iter_t iter;
          bson_iter_t sub_iter;

          if (bson_iter_init_find (&iter, my_bson_doc, "mysubdoc") &&
              (BSON_ITER_HOLDS_DOCUMENT (&iter) || BSON_ITER_HOLDS_ARRAY (&iter)) &&
              bson_iter_recurse (&iter, &sub_iter)) {
             while (bson_iter_next (&sub_iter)) {
                printf ("Found key \"%s\" in sub document.\n", bson_iter_key (&sub_iter));
             }
          }

          bson_iter_t iter;

          if (bson_iter_init (&iter, my_doc) &&
              bson_iter_find_descendant (&iter, "a.b.c.d", &sub_iter)) {
             printf ("The type of a.b.c.d is: %d\n", (int) bson_iter_type (&sub_iter));
          }

          #include <bson/bson.h>

          #define BSON_ITER_HOLDS_DOUBLE(iter) /* ... */

          #define BSON_ITER_HOLDS_UTF8(iter) /* ... */

          #define BSON_ITER_HOLDS_DOCUMENT(iter) /* ... */

          #define BSON_ITER_HOLDS_ARRAY(iter) /* ... */

          #define BSON_ITER_HOLDS_BINARY(iter) /* ... */

          #define BSON_ITER_HOLDS_UNDEFINED(iter) /* ... */

          #define BSON_ITER_HOLDS_OID(iter) /* ... */

          #define BSON_ITER_HOLDS_BOOL(iter) /* ... */

          #define BSON_ITER_HOLDS_DATE_TIME(iter) /* ... */

          #define BSON_ITER_HOLDS_NULL(iter) /* ... */

          #define BSON_ITER_HOLDS_REGEX(iter) /* ... */

          #define BSON_ITER_HOLDS_DBPOINTER(iter) /* ... */

          #define BSON_ITER_HOLDS_CODE(iter) /* ... */

          #define BSON_ITER_HOLDS_SYMBOL(iter) /* ... */

          #define BSON_ITER_HOLDS_CODEWSCOPE(iter) /* ... */

          #define BSON_ITER_HOLDS_INT32(iter) /* ... */

          #define BSON_ITER_HOLDS_TIMESTAMP(iter) /* ... */

          #define BSON_ITER_HOLDS_INT64(iter) /* ... */

          #define BSON_ITER_HOLDS_DECIMAL128(iter) /* ... */

          #define BSON_ITER_HOLDS_MAXKEY(iter) /* ... */

          #define BSON_ITER_HOLDS_MINKEY(iter) /* ... */

          #define BSON_ITER_HOLDS_INT(iter) \
             (BSON_ITER_HOLDS_INT32 (iter) || BSON_ITER_HOLDS_INT64 (iter))

          #define BSON_ITER_HOLDS_NUMBER(iter) \
             (BSON_ITER_HOLDS_INT (iter) || BSON_ITER_HOLDS_DOUBLE (iter))

          #define BSON_ITER_IS_KEY(iter, key) \
             (0 == strcmp ((key), bson_iter_key ((iter))))

          typedef struct {
             /*< private >*/
          } bson_iter_t;