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</div> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_2_12_label aria-expanded=false> <label class=md-nav__title for=__nav_2_12> <span class="md-nav__icon md-icon"></span> Parsing </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../parsing/json_lines/ class=md-nav__link> <span class=md-ellipsis> JSON Lines </span> </a> </li> <li class=md-nav__item> <a href=../parsing/parse_exceptions/ class=md-nav__link> <span class=md-ellipsis> Parsing and Exceptions </span> </a> </li> <li class=md-nav__item> <a href=../parsing/parser_callbacks/ class=md-nav__link> <span class=md-ellipsis> Parser Callbacks </span> </a> </li> <li class=md-nav__item> <a href=../parsing/sax_interface/ class=md-nav__link> <span class=md-ellipsis> SAX Interface </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--active"> <input class="md-nav__toggle md-toggle" type=checkbox id=__toc> <label class="md-nav__link md-nav__link--active" for=__toc> <span class=md-ellipsis> Runtime Assertions </span> <span class="md-nav__icon md-icon"></span> </label> <a href=./ class="md-nav__link md-nav__link--active"> <span class=md-ellipsis> Runtime Assertions </span> </a> <nav class="md-nav md-nav--secondary" aria-label="Table of contents"> <label class=md-nav__title for=__toc> <span class="md-nav__icon md-icon"></span> Table of contents </label> <ul class=md-nav__list data-md-component=toc data-md-scrollfix> <li class=md-nav__item> <a href=#switch-off-runtime-assertions class=md-nav__link> <span class=md-ellipsis> Switch off runtime assertions </span> </a> </li> <li class=md-nav__item> <a href=#change-assertion-behavior class=md-nav__link> <span class=md-ellipsis> Change assertion behavior </span> </a> </li> <li class=md-nav__item> <a href=#function-with-runtime-assertions class=md-nav__link> <span class=md-ellipsis> Function with runtime assertions </span> </a> <nav class=md-nav aria-label="Function with runtime assertions"> <ul class=md-nav__list> <li class=md-nav__item> <a href=#unchecked-object-access-to-a-const-value class=md-nav__link> <span class=md-ellipsis> Unchecked object access to a const value </span> </a> </li> <li class=md-nav__item> <a href=#constructing-from-an-uninitialized-iterator-range class=md-nav__link> <span class=md-ellipsis> Constructing from an uninitialized iterator range </span> </a> </li> <li class=md-nav__item> <a href=#operations-on-uninitialized-iterators class=md-nav__link> <span class=md-ellipsis> Operations on uninitialized iterators </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=#changes class=md-nav__link> <span class=md-ellipsis> Changes </span> </a> <nav class=md-nav aria-label=Changes> <ul class=md-nav__list> <li class=md-nav__item> <a href=#reading-from-a-null-file-or-char-pointer class=md-nav__link> <span class=md-ellipsis> Reading from a null FILE or char pointer </span> </a> </li> </ul> </nav> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../enum_conversion/ class=md-nav__link> <span class=md-ellipsis> Specializing enum conversion </span> </a> </li> <li class=md-nav__item> <a href=../macros/ class=md-nav__link> <span class=md-ellipsis> Supported Macros </span> </a> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_2_16> <div class="md-nav__link md-nav__container"> <a href=../types/ class="md-nav__link "> <span class=md-ellipsis> Types </span> </a> <label class="md-nav__link " for=__nav_2_16 id=__nav_2_16_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_2_16_label aria-expanded=false> <label class=md-nav__title for=__nav_2_16> <span class="md-nav__icon md-icon"></span> Types </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../types/number_handling/ class=md-nav__link> <span class=md-ellipsis> Number Handling </span> </a> </li> </ul> </nav> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_3> <div class="md-nav__link md-nav__container"> <a href=../../integration/ class="md-nav__link "> <span class=md-ellipsis> Integration </span> </a> <label class="md-nav__link " for=__nav_3 id=__nav_3_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=1 aria-labelledby=__nav_3_label aria-expanded=false> <label class=md-nav__title for=__nav_3> <span class="md-nav__icon md-icon"></span> Integration </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../integration/migration_guide/ class=md-nav__link> <span class=md-ellipsis> Migration Guide </span> </a> </li> <li class=md-nav__item> <a href=../../integration/cmake/ class=md-nav__link> <span class=md-ellipsis> CMake </span> </a> </li> <li class=md-nav__item> <a href=../../integration/package_managers/ class=md-nav__link> <span class=md-ellipsis> Package Managers </span> </a> </li> <li class=md-nav__item> <a href=../../integration/pkg-config/ class=md-nav__link> <span class=md-ellipsis> Pkg-config </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4> <label class=md-nav__link for=__nav_4 id=__nav_4_label tabindex=0> <span class=md-ellipsis> API Documentation </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=1 aria-labelledby=__nav_4_label aria-expanded=false> <label class=md-nav__title for=__nav_4> <span class="md-nav__icon md-icon"></span> API Documentation </label> <ul class=md-nav__list data-md-scrollfix> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_1> <div class="md-nav__link md-nav__container"> <a href=../../api/basic_json/ class="md-nav__link "> <span class=md-ellipsis> basic_json </span> </a> <label class="md-nav__link " for=__nav_4_1 id=__nav_4_1_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_4_1_label aria-expanded=false> <label class=md-nav__title for=__nav_4_1> <span class="md-nav__icon md-icon"></span> basic_json </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../api/basic_json/basic_json/ class=md-nav__link> <span class=md-ellipsis> (Constructor) </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/~basic_json/ class=md-nav__link> <span class=md-ellipsis> (Destructor) </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/accept/ class=md-nav__link> <span class=md-ellipsis> accept </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/array/ class=md-nav__link> <span class=md-ellipsis> array </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/array_t/ class=md-nav__link> <span class=md-ellipsis> array_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/at/ class=md-nav__link> <span class=md-ellipsis> at </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/back/ class=md-nav__link> <span class=md-ellipsis> back </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/begin/ class=md-nav__link> <span class=md-ellipsis> begin </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/binary/ class=md-nav__link> <span class=md-ellipsis> binary </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/binary_t/ class=md-nav__link> <span class=md-ellipsis> binary_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/boolean_t/ class=md-nav__link> <span class=md-ellipsis> boolean_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/cbegin/ class=md-nav__link> <span class=md-ellipsis> cbegin </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/cbor_tag_handler_t/ class=md-nav__link> <span class=md-ellipsis> cbor_tag_handler_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/cend/ class=md-nav__link> <span class=md-ellipsis> cend </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/clear/ class=md-nav__link> <span class=md-ellipsis> clear </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/contains/ class=md-nav__link> <span class=md-ellipsis> contains </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/count/ class=md-nav__link> <span class=md-ellipsis> count </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/crbegin/ class=md-nav__link> <span class=md-ellipsis> crbegin </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/crend/ class=md-nav__link> <span class=md-ellipsis> crend </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/default_object_comparator_t/ class=md-nav__link> <span class=md-ellipsis> default_object_comparator_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/diff/ class=md-nav__link> <span class=md-ellipsis> diff </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/dump/ class=md-nav__link> <span class=md-ellipsis> dump </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/emplace/ class=md-nav__link> <span class=md-ellipsis> emplace </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/emplace_back/ class=md-nav__link> <span class=md-ellipsis> emplace_back </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/empty/ class=md-nav__link> <span class=md-ellipsis> empty </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/end/ class=md-nav__link> <span class=md-ellipsis> end </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/erase/ class=md-nav__link> <span class=md-ellipsis> erase </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/error_handler_t/ class=md-nav__link> <span class=md-ellipsis> error_handler_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/exception/ class=md-nav__link> <span class=md-ellipsis> exception </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/find/ class=md-nav__link> <span class=md-ellipsis> find </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/flatten/ class=md-nav__link> <span class=md-ellipsis> flatten </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/from_bjdata/ class=md-nav__link> <span class=md-ellipsis> from_bjdata </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/from_bson/ class=md-nav__link> <span class=md-ellipsis> from_bson </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/from_cbor/ class=md-nav__link> <span class=md-ellipsis> from_cbor </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/from_msgpack/ class=md-nav__link> <span class=md-ellipsis> from_msgpack </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/from_ubjson/ class=md-nav__link> <span class=md-ellipsis> from_ubjson </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/front/ class=md-nav__link> <span class=md-ellipsis> front </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/get/ class=md-nav__link> <span class=md-ellipsis> get </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/get_allocator/ class=md-nav__link> <span class=md-ellipsis> get_allocator </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/get_binary/ class=md-nav__link> <span class=md-ellipsis> get_binary </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/get_ptr/ class=md-nav__link> <span class=md-ellipsis> get_ptr </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/get_ref/ class=md-nav__link> <span class=md-ellipsis> get_ref </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/get_to/ class=md-nav__link> <span class=md-ellipsis> get_to </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/std_hash/ class=md-nav__link> <span class=md-ellipsis> std::hash<basic_json> </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/input_format_t/ class=md-nav__link> <span class=md-ellipsis> input_format_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/insert/ class=md-nav__link> <span class=md-ellipsis> insert </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/invalid_iterator/ class=md-nav__link> <span class=md-ellipsis> invalid_iterator </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_array/ class=md-nav__link> <span class=md-ellipsis> is_array </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_binary/ class=md-nav__link> <span class=md-ellipsis> is_binary </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_boolean/ class=md-nav__link> <span class=md-ellipsis> is_boolean </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_discarded/ class=md-nav__link> <span class=md-ellipsis> is_discarded </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_null/ class=md-nav__link> <span class=md-ellipsis> is_null </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_number/ class=md-nav__link> <span class=md-ellipsis> is_number </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_number_float/ class=md-nav__link> <span class=md-ellipsis> is_number_float </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_number_integer/ class=md-nav__link> <span class=md-ellipsis> is_number_integer </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_number_unsigned/ class=md-nav__link> <span class=md-ellipsis> is_number_unsigned </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_object/ class=md-nav__link> <span class=md-ellipsis> is_object </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_primitive/ class=md-nav__link> <span class=md-ellipsis> is_primitive </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_string/ class=md-nav__link> <span class=md-ellipsis> is_string </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/is_structured/ class=md-nav__link> <span class=md-ellipsis> is_structured </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/items/ class=md-nav__link> <span class=md-ellipsis> items </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/json_base_class_t/ class=md-nav__link> <span class=md-ellipsis> json_base_class_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/json_serializer/ class=md-nav__link> <span class=md-ellipsis> json_serializer </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/max_size/ class=md-nav__link> <span class=md-ellipsis> max_size </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/meta/ class=md-nav__link> <span class=md-ellipsis> meta </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/merge_patch/ class=md-nav__link> <span class=md-ellipsis> merge_patch </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/number_float_t/ class=md-nav__link> <span class=md-ellipsis> number_float_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/number_integer_t/ class=md-nav__link> <span class=md-ellipsis> number_integer_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/number_unsigned_t/ class=md-nav__link> <span class=md-ellipsis> number_unsigned_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/object/ class=md-nav__link> <span class=md-ellipsis> object </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/object_comparator_t/ class=md-nav__link> <span class=md-ellipsis> object_comparator_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/object_t/ class=md-nav__link> <span class=md-ellipsis> object_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_ValueType/ class=md-nav__link> <span class=md-ellipsis> operator ValueType </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_value_t/ class=md-nav__link> <span class=md-ellipsis> operator value_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator%5B%5D/ class=md-nav__link> <span class=md-ellipsis> operator[] </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator%3D/ class=md-nav__link> <span class=md-ellipsis> operator= </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator%2B%3D/ class=md-nav__link> <span class=md-ellipsis> operator+= </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_eq/ class=md-nav__link> <span class=md-ellipsis> operator== </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_ne/ class=md-nav__link> <span class=md-ellipsis> operator!= </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_lt/ class=md-nav__link> <span class=md-ellipsis> operator< </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_gt/ class=md-nav__link> <span class=md-ellipsis> operator> </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_le/ class=md-nav__link> <span class=md-ellipsis> operator<= </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_ge/ class=md-nav__link> <span class=md-ellipsis> operator>= </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/operator_spaceship/ class=md-nav__link> <span class=md-ellipsis> operator<=> </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/out_of_range/ class=md-nav__link> <span class=md-ellipsis> out_of_range </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/other_error/ class=md-nav__link> <span class=md-ellipsis> other_error </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/parse/ class=md-nav__link> <span class=md-ellipsis> parse </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/parse_error/ class=md-nav__link> <span class=md-ellipsis> parse_error </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/parse_event_t/ class=md-nav__link> <span class=md-ellipsis> parse_event_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/parser_callback_t/ class=md-nav__link> <span class=md-ellipsis> parser_callback_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/patch/ class=md-nav__link> <span class=md-ellipsis> patch </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/patch_inplace/ class=md-nav__link> <span class=md-ellipsis> patch_inplace </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/push_back/ class=md-nav__link> <span class=md-ellipsis> push_back </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/rbegin/ class=md-nav__link> <span class=md-ellipsis> rbegin </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/rend/ class=md-nav__link> <span class=md-ellipsis> rend </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/sax_parse/ class=md-nav__link> <span class=md-ellipsis> sax_parse </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/size/ class=md-nav__link> <span class=md-ellipsis> size </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/string_t/ class=md-nav__link> <span class=md-ellipsis> string_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/swap/ class=md-nav__link> <span class=md-ellipsis> swap </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/std_swap/ class=md-nav__link> <span class=md-ellipsis> std::swap<basic_json> </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/to_bjdata/ class=md-nav__link> <span class=md-ellipsis> to_bjdata </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/to_bson/ class=md-nav__link> <span class=md-ellipsis> to_bson </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/to_cbor/ class=md-nav__link> <span class=md-ellipsis> to_cbor </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/to_msgpack/ class=md-nav__link> <span class=md-ellipsis> to_msgpack </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/to_string/ class=md-nav__link> <span class=md-ellipsis> to_string </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/to_ubjson/ class=md-nav__link> <span class=md-ellipsis> to_ubjson </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/type/ class=md-nav__link> <span class=md-ellipsis> type </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/type_error/ class=md-nav__link> <span class=md-ellipsis> type_error </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/type_name/ class=md-nav__link> <span class=md-ellipsis> type_name </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/unflatten/ class=md-nav__link> <span class=md-ellipsis> unflatten </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/update/ class=md-nav__link> <span class=md-ellipsis> update </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/value/ class=md-nav__link> <span class=md-ellipsis> value </span> </a> </li> <li class=md-nav__item> <a href=../../api/basic_json/value_t/ class=md-nav__link> <span class=md-ellipsis> value_t </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_2> <div class="md-nav__link md-nav__container"> <a href=../../api/byte_container_with_subtype/ class="md-nav__link "> <span class=md-ellipsis> byte_container_with_subtype </span> </a> <label class="md-nav__link " for=__nav_4_2 id=__nav_4_2_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_4_2_label aria-expanded=false> <label class=md-nav__title for=__nav_4_2> <span class="md-nav__icon md-icon"></span> byte_container_with_subtype </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../api/byte_container_with_subtype/byte_container_with_subtype/ class=md-nav__link> <span class=md-ellipsis> (constructor) </span> </a> </li> <li class=md-nav__item> <a href=../../api/byte_container_with_subtype/clear_subtype/ class=md-nav__link> <span class=md-ellipsis> clear_subtype </span> </a> </li> <li class=md-nav__item> <a href=../../api/byte_container_with_subtype/has_subtype/ class=md-nav__link> <span class=md-ellipsis> has_subtype </span> </a> </li> <li class=md-nav__item> <a href=../../api/byte_container_with_subtype/set_subtype/ class=md-nav__link> <span class=md-ellipsis> set_subtype </span> </a> </li> <li class=md-nav__item> <a href=../../api/byte_container_with_subtype/subtype/ class=md-nav__link> <span class=md-ellipsis> subtype </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_3> <div class="md-nav__link md-nav__container"> <a href=../../api/adl_serializer/ class="md-nav__link "> <span class=md-ellipsis> adl_serializer </span> </a> <label class="md-nav__link " for=__nav_4_3 id=__nav_4_3_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_4_3_label aria-expanded=false> <label class=md-nav__title for=__nav_4_3> <span class="md-nav__icon md-icon"></span> adl_serializer </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../api/adl_serializer/from_json/ class=md-nav__link> <span class=md-ellipsis> from_json </span> </a> </li> <li class=md-nav__item> <a href=../../api/adl_serializer/to_json/ class=md-nav__link> <span class=md-ellipsis> to_json </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../../api/json/ class=md-nav__link> <span class=md-ellipsis> json </span> </a> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_5> <div class="md-nav__link md-nav__container"> <a href=../../api/json_pointer/ class="md-nav__link "> <span class=md-ellipsis> json_pointer </span> </a> <label class="md-nav__link " for=__nav_4_5 id=__nav_4_5_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_4_5_label aria-expanded=false> <label class=md-nav__title for=__nav_4_5> <span class="md-nav__icon md-icon"></span> json_pointer </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../api/json_pointer/json_pointer/ class=md-nav__link> <span class=md-ellipsis> (Constructor) </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/back/ class=md-nav__link> <span class=md-ellipsis> back </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/empty/ class=md-nav__link> <span class=md-ellipsis> empty </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/operator_string_t/ class=md-nav__link> <span class=md-ellipsis> operator string_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/operator_eq/ class=md-nav__link> <span class=md-ellipsis> operator== </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/operator_ne/ class=md-nav__link> <span class=md-ellipsis> operator!= </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/operator_slash/ class=md-nav__link> <span class=md-ellipsis> operator/ </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/operator_slasheq/ class=md-nav__link> <span class=md-ellipsis> operator/= </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/parent_pointer/ class=md-nav__link> <span class=md-ellipsis> parent_pointer </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/pop_back/ class=md-nav__link> <span class=md-ellipsis> pop_back </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/push_back/ class=md-nav__link> <span class=md-ellipsis> push_back </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/string_t/ class=md-nav__link> <span class=md-ellipsis> string_t </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_pointer/to_string/ class=md-nav__link> <span class=md-ellipsis> to_string </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_6> <div class="md-nav__link md-nav__container"> <a href=../../api/json_sax/ class="md-nav__link "> <span class=md-ellipsis> json_sax </span> </a> <label class="md-nav__link " for=__nav_4_6 id=__nav_4_6_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_4_6_label aria-expanded=false> <label class=md-nav__title for=__nav_4_6> <span class="md-nav__icon md-icon"></span> json_sax </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../api/json_sax/binary/ class=md-nav__link> <span class=md-ellipsis> binary </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/boolean/ class=md-nav__link> <span class=md-ellipsis> boolean </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/end_array/ class=md-nav__link> <span class=md-ellipsis> end_array </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/end_object/ class=md-nav__link> <span class=md-ellipsis> end_object </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/key/ class=md-nav__link> <span class=md-ellipsis> key </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/null/ class=md-nav__link> <span class=md-ellipsis> null </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/number_float/ class=md-nav__link> <span class=md-ellipsis> number_float </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/number_integer/ class=md-nav__link> <span class=md-ellipsis> number_integer </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/number_unsigned/ class=md-nav__link> <span class=md-ellipsis> number_unsigned </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/parse_error/ class=md-nav__link> <span class=md-ellipsis> parse_error </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/start_array/ class=md-nav__link> <span class=md-ellipsis> start_array </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/start_object/ class=md-nav__link> <span class=md-ellipsis> start_object </span> </a> </li> <li class=md-nav__item> <a href=../../api/json_sax/string/ class=md-nav__link> <span class=md-ellipsis> string </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../../api/operator_ltlt/ class=md-nav__link> <span class=md-ellipsis> operator<<(basic_json) </span> </a> </li> <li class=md-nav__item> <a href=../../api/operator_ltlt/ class=md-nav__link> <span class=md-ellipsis> operator<<(basic_json) </span> </a> </li> <li class=md-nav__item> <a href=../../api/operator_gtgt/ class=md-nav__link> <span class=md-ellipsis> operator>>(basic_json) </span> </a> </li> <li class=md-nav__item> <a href=../../api/operator_literal_json/ class=md-nav__link> <span class=md-ellipsis> operator""_json </span> </a> </li> <li class=md-nav__item> <a href=../../api/operator_literal_json_pointer/ class=md-nav__link> <span class=md-ellipsis> operator""_json_pointer </span> </a> </li> <li class=md-nav__item> <a href=../../api/ordered_json/ class=md-nav__link> <span class=md-ellipsis> ordered_json </span> </a> </li> <li class=md-nav__item> <a href=../../api/ordered_map/ class=md-nav__link> <span class=md-ellipsis> ordered_map </span> </a> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_14> <div class="md-nav__link md-nav__container"> <a href=../../api/macros/ class="md-nav__link "> <span class=md-ellipsis> macros </span> </a> <label class="md-nav__link " for=__nav_4_14 id=__nav_4_14_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_4_14_label aria-expanded=false> <label class=md-nav__title for=__nav_4_14> <span class="md-nav__icon md-icon"></span> macros </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../api/macros/json_assert/ class=md-nav__link> <span class=md-ellipsis> JSON_ASSERT </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_throw_user/ class=md-nav__link> <span class=md-ellipsis> JSON_CATCH_USER </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_diagnostics/ class=md-nav__link> <span class=md-ellipsis> JSON_DIAGNOSTICS </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_disable_enum_serialization/ class=md-nav__link> <span class=md-ellipsis> JSON_DISABLE_ENUM_SERIALIZATION </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_cpp_11/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_CPP_11 </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_cpp_11/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_CPP_11 </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_cpp_11/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_CPP_11 </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_cpp_11/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_CPP_11 </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_filesystem/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_EXPERIMENTAL_FILESYSTEM </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_filesystem/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_EXPERIMENTAL_FILESYSTEM </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_ranges/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_RANGES </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_static_rtti/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_STATIC_RTTI </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_has_three_way_comparison/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_THREE_WAY_COMPARISON </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_noexception/ class=md-nav__link> <span class=md-ellipsis> JSON_NOEXCEPTION </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_no_io/ class=md-nav__link> <span class=md-ellipsis> JSON_NO_IO </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_skip_library_version_check/ class=md-nav__link> <span class=md-ellipsis> JSON_SKIP_LIBRARY_VERSION_CHECK </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_skip_unsupported_compiler_check/ class=md-nav__link> <span class=md-ellipsis> JSON_SKIP_UNSUPPORTED_COMPILER_CHECK </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_throw_user/ class=md-nav__link> <span class=md-ellipsis> JSON_CATCH_USER </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_throw_user/ class=md-nav__link> <span class=md-ellipsis> JSON_CATCH_USER </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_use_global_udls/ class=md-nav__link> <span class=md-ellipsis> JSON_USE_GLOBAL_UDLS </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_use_implicit_conversions/ class=md-nav__link> <span class=md-ellipsis> JSON_USE_IMPLICIT_CONVERSIONS </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/json_use_legacy_discarded_value_comparison/ class=md-nav__link> <span class=md-ellipsis> JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_derived_type/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_derived_type/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_derived_type/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_derived_type/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_derived_type/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_derived_type/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_type_intrusive/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_type_intrusive/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_type_intrusive/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_type_non_intrusive/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_type_non_intrusive/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_define_type_non_intrusive/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_json_namespace/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_NAMESPACE </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_json_namespace_begin/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_NAMESPACE_BEGIN </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_json_namespace_begin/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_NAMESPACE_BEGIN </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_json_namespace_no_version/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_NAMESPACE_NO_VERSION </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_json_serialize_enum/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_SERIALIZE_ENUM </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_json_version_major/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_VERSION_MAJOR </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_json_version_major/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_VERSION_MAJOR </span> </a> </li> <li class=md-nav__item> <a href=../../api/macros/nlohmann_json_version_major/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_VERSION_MAJOR </span> </a> </li> </ul> </nav> </li> </ul> </nav> </li> </ul> </nav> </div> </div> </div> <div class="md-sidebar md-sidebar--secondary" data-md-component=sidebar data-md-type=toc> <div class=md-sidebar__scrollwrap> <div class=md-sidebar__inner> <nav class="md-nav md-nav--secondary" aria-label="Table of contents"> <label class=md-nav__title for=__toc> <span class="md-nav__icon md-icon"></span> Table of contents </label> <ul class=md-nav__list data-md-component=toc data-md-scrollfix> <li class=md-nav__item> <a href=#switch-off-runtime-assertions class=md-nav__link> <span class=md-ellipsis> Switch off runtime assertions </span> </a> </li> <li class=md-nav__item> <a href=#change-assertion-behavior class=md-nav__link> <span class=md-ellipsis> Change assertion behavior </span> </a> </li> <li class=md-nav__item> <a href=#function-with-runtime-assertions class=md-nav__link> <span class=md-ellipsis> Function with runtime assertions </span> </a> <nav class=md-nav aria-label="Function with runtime assertions"> <ul class=md-nav__list> <li class=md-nav__item> <a href=#unchecked-object-access-to-a-const-value class=md-nav__link> <span class=md-ellipsis> Unchecked object access to a const value </span> </a> </li> <li class=md-nav__item> <a href=#constructing-from-an-uninitialized-iterator-range class=md-nav__link> <span class=md-ellipsis> Constructing from an uninitialized iterator range </span> </a> </li> <li class=md-nav__item> <a href=#operations-on-uninitialized-iterators class=md-nav__link> <span class=md-ellipsis> Operations on uninitialized iterators </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=#changes class=md-nav__link> <span class=md-ellipsis> Changes </span> </a> <nav class=md-nav aria-label=Changes> <ul class=md-nav__list> <li class=md-nav__item> <a href=#reading-from-a-null-file-or-char-pointer class=md-nav__link> <span class=md-ellipsis> Reading from a null FILE or char pointer </span> </a> </li> </ul> </nav> </li> </ul> </nav> </div> </div> </div> <div class=md-content data-md-component=content> <article class="md-content__inner md-typeset"> <a href=https://github.com/nlohmann/json/edit/develop/docs/mkdocs/docs/features/assertions.md title="Edit this page" class="md-content__button md-icon"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M10 20H6V4h7v5h5v3.1l2-2V8l-6-6H6c-1.1 0-2 .9-2 2v16c0 1.1.9 2 2 2h4zm10.2-7c.1 0 .3.1.4.2l1.3 1.3c.2.2.2.6 0 .8l-1 1-2.1-2.1 1-1c.1-.1.2-.2.4-.2m0 3.9L14.1 23H12v-2.1l6.1-6.1z"/></svg> </a> <a href=https://github.com/nlohmann/json/raw/develop/docs/mkdocs/docs/features/assertions.md title="View source of this page" class="md-content__button md-icon"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M17 18c.56 0 1 .44 1 1s-.44 1-1 1-1-.44-1-1 .44-1 1-1m0-3c-2.73 0-5.06 1.66-6 4 .94 2.34 3.27 4 6 4s5.06-1.66 6-4c-.94-2.34-3.27-4-6-4m0 6.5a2.5 2.5 0 0 1-2.5-2.5 2.5 2.5 0 0 1 2.5-2.5 2.5 2.5 0 0 1 2.5 2.5 2.5 2.5 0 0 1-2.5 2.5M9.27 20H6V4h7v5h5v4.07c.7.08 1.36.25 2 .49V8l-6-6H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h4.5a8.2 8.2 0 0 1-1.23-2"/></svg> </a> <h1 id=runtime-assertions>Runtime Assertions<a class=headerlink href=#runtime-assertions title="Permanent link">¶</a></h1> <p>The code contains numerous debug assertions to ensure class invariants are valid or to detect undefined behavior. Whereas the former class invariants are nothing to be concerned of, the latter checks for undefined behavior are to detect bugs in client code.</p> <h2 id=switch-off-runtime-assertions>Switch off runtime assertions<a class=headerlink href=#switch-off-runtime-assertions title="Permanent link">¶</a></h2> <p>Runtime assertions can be switched off by defining the preprocessor macro <code>NDEBUG</code> (see the <a href=https://en.cppreference.com/w/cpp/error/assert>documentation of assert</a>) which is the default for release builds.</p> <h2 id=change-assertion-behavior>Change assertion behavior<a class=headerlink href=#change-assertion-behavior title="Permanent link">¶</a></h2> <p>The behavior of runtime assertions can be changes by defining macro <a href=../../api/macros/json_assert/ ><code>JSON_ASSERT(x)</code></a> before including the <code>json.hpp</code> header.</p> <h2 id=function-with-runtime-assertions>Function with runtime assertions<a class=headerlink href=#function-with-runtime-assertions title="Permanent link">¶</a></h2> <h3 id=unchecked-object-access-to-a-const-value>Unchecked object access to a const value<a class=headerlink href=#unchecked-object-access-to-a-const-value title="Permanent link">¶</a></h3> <p>Function <a href=../../api/basic_json/operator%5B%5D/ ><code>operator[]</code></a> implements unchecked access for objects. Whereas a missing key is added in case of non-const objects, accessing a const object with a missing key is undefined behavior (think of a dereferenced null pointer) and yields a runtime assertion.</p> <p>If you are not sure whether an element in an object exists, use checked access with the <a href=../../api/basic_json/at/ ><code>at</code> function</a> or call the <a href=../../api/basic_json/contains/ ><code>contains</code> function</a> before.</p> <p>See also the documentation on <a href=../element_access/ >element access</a>.</p> <details class=example> <summary>Example 1: Missing object key</summary> <p>The following code will trigger an assertion at runtime:</p> <div class=highlight><pre><span></span><code><span class=cp>#include</span><span class=w> </span><span class=cpf><nlohmann/json.hpp></span> |
| |
| <span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span> |
| |
| <span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span> |
| <span class=p>{</span> |
| <span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=p>{{</span><span class=s>"key"</span><span class=p>,</span><span class=w> </span><span class=s>"value"</span><span class=p>}};</span> |
| <span class=w> </span><span class=k>auto</span><span class=w> </span><span class=n>v</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>"missing"</span><span class=p>];</span> |
| <span class=p>}</span> |
| </code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>Assertion failed: (m_value.object->find(key) != m_value.object->end()), function operator[], file json.hpp, line 2144. |
| </code></pre></div> </details> <h3 id=constructing-from-an-uninitialized-iterator-range>Constructing from an uninitialized iterator range<a class=headerlink href=#constructing-from-an-uninitialized-iterator-range title="Permanent link">¶</a></h3> <p>Constructing a JSON value from an iterator range (see <a href=../../api/basic_json/basic_json/ >constructor</a>) with an uninitialized iterator is undefined behavior and yields a runtime assertion.</p> <details class=example> <summary>Example 2: Uninitialized iterator range</summary> <p>The following code will trigger an assertion at runtime:</p> <div class=highlight><pre><span></span><code><span class=cp>#include</span><span class=w> </span><span class=cpf><nlohmann/json.hpp></span> |
| |
| <span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span> |
| |
| <span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span> |
| <span class=p>{</span> |
| <span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>iterator</span><span class=w> </span><span class=n>it1</span><span class=p>,</span><span class=w> </span><span class=n>it2</span><span class=p>;</span> |
| <span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=p>(</span><span class=n>it1</span><span class=p>,</span><span class=w> </span><span class=n>it2</span><span class=p>);</span> |
| <span class=p>}</span> |
| </code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>Assertion failed: (m_object != nullptr), function operator++, file iter_impl.hpp, line 368. |
| </code></pre></div> </details> <h3 id=operations-on-uninitialized-iterators>Operations on uninitialized iterators<a class=headerlink href=#operations-on-uninitialized-iterators title="Permanent link">¶</a></h3> <p>Any operation on uninitialized iterators (i.e., iterators that are not associated with any JSON value) is undefined behavior and yields a runtime assertion.</p> <details class=example> <summary>Example 3: Uninitialized iterator</summary> <p>The following code will trigger an assertion at runtime:</p> <div class=highlight><pre><span></span><code><span class=cp>#include</span><span class=w> </span><span class=cpf><nlohmann/json.hpp></span> |
| |
| <span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span> |
| |
| <span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span> |
| <span class=p>{</span> |
| <span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>iterator</span><span class=w> </span><span class=n>it</span><span class=p>;</span> |
| <span class=w> </span><span class=o>++</span><span class=n>it</span><span class=p>;</span> |
| <span class=p>}</span> |
| </code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>Assertion failed: (m_object != nullptr), function operator++, file iter_impl.hpp, line 368. |
| </code></pre></div> </details> <h2 id=changes>Changes<a class=headerlink href=#changes title="Permanent link">¶</a></h2> <h3 id=reading-from-a-null-file-or-char-pointer>Reading from a null <code>FILE</code> or <code>char</code> pointer<a class=headerlink href=#reading-from-a-null-file-or-char-pointer title="Permanent link">¶</a></h3> <p>Reading from a null <code class=highlight><span class=kt>FILE</span></code> or <code class=highlight><span class=kt>char</span></code> pointer in C++ is undefined behavior. Until version 3.11.4, this library asserted that the pointer was not <code>nullptr</code> using a runtime assertion. If assertions were disabled, this would result in undefined behavior. Since version 3.11.4, this library checks for <code>nullptr</code> and throws a <a href=../../home/exceptions/#jsonexceptionparse_error101><code>parse_error.101</code></a> to prevent the undefined behavior.</p> <details class=example> <summary>Example 4: Reading from null pointer</summary> <p>The following code will trigger an assertion at runtime:</p> <div class=highlight><pre><span></span><code><span class=cp>#include</span><span class=w> </span><span class=cpf><iostream></span> |
| <span class=cp>#include</span><span class=w> </span><span class=cpf><nlohmann/json.hpp></span> |
| |
| <span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span> |
| |
| <span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span> |
| <span class=p>{</span> |
| <span class=w> </span><span class=n>std</span><span class=o>::</span><span class=kt>FILE</span><span class=o>*</span><span class=w> </span><span class=n>f</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>fopen</span><span class=p>(</span><span class=s>"nonexistent_file.json"</span><span class=p>,</span><span class=w> </span><span class=s>"r"</span><span class=p>);</span> |
| <span class=w> </span><span class=k>try</span><span class=w> </span><span class=p>{</span> |
| <span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=n>f</span><span class=p>);</span> |
| <span class=w> </span><span class=p>}</span><span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=n>std</span><span class=o>::</span><span class=n>exception</span><span class=o>&</span><span class=w> </span><span class=n>e</span><span class=p>)</span><span class=w> </span><span class=p>{</span> |
| <span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cerr</span><span class=w> </span><span class=o><<</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o><<</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span> |
| <span class=w> </span><span class=p>}</span> |
| <span class=p>}</span> |
| </code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.101] parse error: attempting to parse an empty input; check that your input string or stream contains the expected JSON |
| </code></pre></div> </details> <aside class=md-source-file> <span class=md-source-file__fact> <span class=md-icon title="Last update"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M21 13.1c-.1 0-.3.1-.4.2l-1 1 2.1 2.1 1-1c.2-.2.2-.6 0-.8l-1.3-1.3c-.1-.1-.2-.2-.4-.2m-1.9 1.8-6.1 6V23h2.1l6.1-6.1zM12.5 7v5.2l4 2.4-1 1L11 13V7zM11 21.9c-5.1-.5-9-4.8-9-9.9C2 6.5 6.5 2 12 2c5.3 0 9.6 4.1 10 9.3-.3-.1-.6-.2-1-.2s-.7.1-1 .2C19.6 7.2 16.2 4 12 4c-4.4 0-8 3.6-8 8 0 4.1 3.1 7.5 7.1 7.9l-.1.2z"/></svg> </span> <span class="git-revision-date-localized-plugin git-revision-date-localized-plugin-date">January 3, 2025</span> </span> </aside> </article> </div> <script>var tabs=__md_get("__tabs");if(Array.isArray(tabs))e:for(var set of document.querySelectorAll(".tabbed-set")){var labels=set.querySelector(".tabbed-labels");for(var tab of tabs)for(var label of labels.getElementsByTagName("label"))if(label.innerText.trim()===tab){var input=document.getElementById(label.htmlFor);input.checked=!0;continue e}}</script> <script>var target=document.getElementById(location.hash.slice(1));target&&target.name&&(target.checked=target.name.startsWith("__tabbed_"))</script> </div> <button type=button class="md-top md-icon" data-md-component=top hidden> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M13 20h-2V8l-5.5 5.5-1.42-1.42L12 4.16l7.92 7.92-1.42 1.42L13 8z"/></svg> Back to top </button> </main> <footer class=md-footer> <div class="md-footer-meta md-typeset"> <div class="md-footer-meta__inner md-grid"> <div class=md-copyright> <div class=md-copyright__highlight> Copyright © 2013 - 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