rb_hash_delete_if 713 ext/dbm/dbm.c      return rb_hash_delete_if(fdbm_to_hash(obj));
rb_hash_delete_if 916 ext/gdbm/gdbm.c     return rb_hash_delete_if(fgdbm_to_hash(obj));
rb_hash_delete_if 712 ext/sdbm/init.c     return rb_hash_delete_if(fsdbm_to_hash(obj));
rb_hash_delete_if 484 hash.c             rb_hash_delete_if(hash);
rb_hash_delete_if 493 hash.c             return rb_hash_delete_if(rb_obj_dup(hash));
rb_hash_delete_if 1574 hash.c             return rb_hash_delete_if(env_to_hash());