:sig bool DValue::has(String s) const :params s : child key to test return value : true when the dereferenced value is map-shaped and contains the key :see >types 0_DValue 2_DValue_key 2_DValue_get_by_path :content Checks for a child key without creating it. Returns false for scalars and missing keys. :example DValue user; user["name"] = "Ada"; print(user.has("name") ? "yes\n" : "no\n");