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md-icon"></span> Element Access </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../../features/element_access/unchecked_access/ class=md-nav__link> <span class=md-ellipsis> Unchecked access: operator[] </span> </a> </li> <li class=md-nav__item> <a href=../../../features/element_access/checked_access/ class=md-nav__link> <span class=md-ellipsis> Checked access: at </span> </a> </li> <li class=md-nav__item> <a href=../../../features/element_access/default_value/ class=md-nav__link> <span class=md-ellipsis> Access with default value: value </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../../../features/iterators/ class=md-nav__link> <span class=md-ellipsis> Iterators </span> </a> </li> <li class=md-nav__item> <a href=../../../features/merge_patch/ class=md-nav__link> <span class=md-ellipsis> JSON Merge Patch </span> </a> </li> <li class=md-nav__item> <a href=../../../features/json_patch/ class=md-nav__link> <span class=md-ellipsis> JSON Patch and Diff </span> </a> </li> <li class=md-nav__item> <a href=../../../features/json_pointer/ class=md-nav__link> <span class=md-ellipsis> JSON Pointer </span> </a> </li> <li class=md-nav__item> <a href=../../../features/modifying_values/ class=md-nav__link> <span class=md-ellipsis> Modifying values </span> </a> </li> <li class=md-nav__item> <a href=../../../features/modules/ class=md-nav__link> <span class=md-ellipsis> Modules </span> </a> </li> <li class=md-nav__item> <a href=../../../features/namespace/ class=md-nav__link> <span class=md-ellipsis> nlohmann Namespace </span> </a> </li> <li class=md-nav__item> <a href=../../../features/object_order/ class=md-nav__link> <span class=md-ellipsis> Object Order </span> </a> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_2_17> <div class="md-nav__link md-nav__container"> <a href=../../../features/parsing/ class="md-nav__link "> <span class=md-ellipsis> Parsing </span> </a> <label class="md-nav__link " for=__nav_2_17 id=__nav_2_17_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_17_label aria-expanded=false> <label class=md-nav__title for=__nav_2_17> <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=../../../features/parsing/json_lines/ class=md-nav__link> <span class=md-ellipsis> JSON Lines </span> </a> </li> <li class=md-nav__item> <a href=../../../features/parsing/parse_exceptions/ class=md-nav__link> <span class=md-ellipsis> Parsing and Exceptions </span> </a> </li> <li class=md-nav__item> <a href=../../../features/parsing/parser_callbacks/ class=md-nav__link> <span class=md-ellipsis> Parser Callbacks </span> </a> </li> <li class=md-nav__item> <a href=../../../features/parsing/sax_interface/ class=md-nav__link> <span class=md-ellipsis> SAX Interface </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../../../features/assertions/ class=md-nav__link> <span class=md-ellipsis> Runtime Assertions </span> </a> </li> <li class=md-nav__item> <a href=../../../features/serialization/ class=md-nav__link> <span class=md-ellipsis> Serialization </span> </a> </li> <li class=md-nav__item> <a href=../../../features/enum_conversion/ class=md-nav__link> <span class=md-ellipsis> Specializing enum conversion </span> </a> </li> <li class=md-nav__item> <a href=../../../features/macros/ class=md-nav__link> <span class=md-ellipsis> Supported Macros </span> </a> </li> <li class=md-nav__item> <a href=../../../features/trailing_commas/ class=md-nav__link> <span class=md-ellipsis> Trailing Commas </span> </a> </li> <li class="md-nav__item md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_2_23> <div class="md-nav__link md-nav__container"> <a href=../../../features/types/ class="md-nav__link "> <span class=md-ellipsis> Types </span> </a> <label class="md-nav__link " for=__nav_2_23 id=__nav_2_23_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_23_label aria-expanded=false> <label class=md-nav__title for=__nav_2_23> <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=../../../features/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--active md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4 checked> <label class=md-nav__link for=__nav_4 id=__nav_4_label tabindex> <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=true> <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--active md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_1 checked> <div class="md-nav__link md-nav__container"> <a href=../ 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=true> <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=../basic_json/ class=md-nav__link> <span class=md-ellipsis> (Constructor) </span> </a> </li> <li class=md-nav__item> <a href=../~basic_json/ class=md-nav__link> <span class=md-ellipsis> (Destructor) </span> </a> </li> <li class=md-nav__item> <a href=../accept/ class=md-nav__link> <span class=md-ellipsis> accept </span> </a> </li> <li class=md-nav__item> <a href=../array/ class=md-nav__link> <span class=md-ellipsis> array </span> </a> </li> <li class=md-nav__item> <a href=../array_t/ class=md-nav__link> <span class=md-ellipsis> array_t </span> </a> </li> <li class=md-nav__item> <a href=../at/ class=md-nav__link> <span class=md-ellipsis> at </span> </a> </li> <li class=md-nav__item> <a href=../back/ class=md-nav__link> <span class=md-ellipsis> back </span> </a> </li> <li class=md-nav__item> <a href=../begin/ class=md-nav__link> <span class=md-ellipsis> begin </span> </a> </li> <li class=md-nav__item> <a href=../binary/ class=md-nav__link> <span class=md-ellipsis> binary </span> </a> </li> <li class=md-nav__item> <a href=../binary_t/ class=md-nav__link> <span class=md-ellipsis> binary_t </span> </a> </li> <li class=md-nav__item> <a href=../boolean_t/ class=md-nav__link> <span class=md-ellipsis> boolean_t </span> </a> </li> <li class=md-nav__item> <a href=../cbegin/ class=md-nav__link> <span class=md-ellipsis> cbegin </span> </a> </li> <li class=md-nav__item> <a href=../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=../cend/ class=md-nav__link> <span class=md-ellipsis> cend </span> </a> </li> <li class=md-nav__item> <a href=../clear/ class=md-nav__link> <span class=md-ellipsis> clear </span> </a> </li> <li class=md-nav__item> <a href=../contains/ class=md-nav__link> <span class=md-ellipsis> contains </span> </a> </li> <li class=md-nav__item> <a href=../count/ class=md-nav__link> <span class=md-ellipsis> count </span> </a> </li> <li class=md-nav__item> <a href=../crbegin/ class=md-nav__link> <span class=md-ellipsis> crbegin </span> </a> </li> <li class=md-nav__item> <a href=../crend/ class=md-nav__link> <span class=md-ellipsis> crend </span> </a> </li> <li class=md-nav__item> <a href=../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=../diff/ class=md-nav__link> <span class=md-ellipsis> diff </span> </a> </li> <li class=md-nav__item> <a href=../dump/ class=md-nav__link> <span class=md-ellipsis> dump </span> </a> </li> <li class=md-nav__item> <a href=../emplace/ class=md-nav__link> <span class=md-ellipsis> emplace </span> </a> </li> <li class=md-nav__item> <a href=../emplace_back/ class=md-nav__link> <span class=md-ellipsis> emplace_back </span> </a> </li> <li class=md-nav__item> <a href=../empty/ class=md-nav__link> <span class=md-ellipsis> empty </span> </a> </li> <li class=md-nav__item> <a href=../end/ class=md-nav__link> <span class=md-ellipsis> end </span> </a> </li> <li class=md-nav__item> <a href=../end_pos/ class=md-nav__link> <span class=md-ellipsis> end_pos </span> </a> </li> <li class=md-nav__item> <a href=../erase/ class=md-nav__link> <span class=md-ellipsis> erase </span> </a> </li> <li class=md-nav__item> <a href=../error_handler_t/ class=md-nav__link> <span class=md-ellipsis> error_handler_t </span> </a> </li> <li class=md-nav__item> <a href=../exception/ class=md-nav__link> <span class=md-ellipsis> exception </span> </a> </li> <li class=md-nav__item> <a href=../find/ class=md-nav__link> <span class=md-ellipsis> find </span> </a> </li> <li class=md-nav__item> <a href=../flatten/ class=md-nav__link> <span class=md-ellipsis> flatten </span> </a> </li> <li class=md-nav__item> <a href=../format_as/ class=md-nav__link> <span class=md-ellipsis> format_as </span> </a> </li> <li class=md-nav__item> <a href=../from_bjdata/ class=md-nav__link> <span class=md-ellipsis> from_bjdata </span> </a> </li> <li class=md-nav__item> <a href=../from_bson/ class=md-nav__link> <span class=md-ellipsis> from_bson </span> </a> </li> <li class=md-nav__item> <a href=../from_cbor/ class=md-nav__link> <span class=md-ellipsis> from_cbor </span> </a> </li> <li class=md-nav__item> <a href=../from_msgpack/ class=md-nav__link> <span class=md-ellipsis> from_msgpack </span> </a> </li> <li class=md-nav__item> <a href=../from_ubjson/ class=md-nav__link> <span class=md-ellipsis> from_ubjson </span> </a> </li> <li class=md-nav__item> <a href=../front/ class=md-nav__link> <span class=md-ellipsis> front </span> </a> </li> <li class=md-nav__item> <a href=../get/ class=md-nav__link> <span class=md-ellipsis> get </span> </a> </li> <li class=md-nav__item> <a href=../get_allocator/ class=md-nav__link> <span class=md-ellipsis> get_allocator </span> </a> </li> <li class=md-nav__item> <a href=../get_binary/ class=md-nav__link> <span class=md-ellipsis> get_binary </span> </a> </li> <li class=md-nav__item> <a href=../get_ptr/ class=md-nav__link> <span class=md-ellipsis> get_ptr </span> </a> </li> <li class=md-nav__item> <a href=../get_ref/ class=md-nav__link> <span class=md-ellipsis> get_ref </span> </a> </li> <li class=md-nav__item> <a href=../get_to/ class=md-nav__link> <span class=md-ellipsis> get_to </span> </a> </li> <li class=md-nav__item> <a href=../std_formatter/ class=md-nav__link> <span class=md-ellipsis> std::formatter&lt;basic_json&gt; </span> </a> </li> <li class=md-nav__item> <a href=../std_hash/ class=md-nav__link> <span class=md-ellipsis> std::hash&lt;basic_json&gt; </span> </a> </li> <li class=md-nav__item> <a href=../input_format_t/ class=md-nav__link> <span class=md-ellipsis> input_format_t </span> </a> </li> <li class=md-nav__item> <a href=../insert/ class=md-nav__link> <span class=md-ellipsis> insert </span> </a> </li> <li class=md-nav__item> <a href=../invalid_iterator/ class=md-nav__link> <span class=md-ellipsis> invalid_iterator </span> </a> </li> <li class=md-nav__item> <a href=../is_array/ class=md-nav__link> <span class=md-ellipsis> is_array </span> </a> </li> <li class=md-nav__item> <a href=../is_binary/ class=md-nav__link> <span class=md-ellipsis> is_binary </span> </a> </li> <li class=md-nav__item> <a href=../is_boolean/ class=md-nav__link> <span class=md-ellipsis> is_boolean </span> </a> </li> <li class=md-nav__item> <a href=../is_discarded/ class=md-nav__link> <span class=md-ellipsis> is_discarded </span> </a> </li> <li class=md-nav__item> <a href=../is_null/ class=md-nav__link> <span class=md-ellipsis> is_null </span> </a> </li> <li class=md-nav__item> <a href=../is_number/ class=md-nav__link> <span class=md-ellipsis> is_number </span> </a> </li> <li class=md-nav__item> <a href=../is_number_float/ class=md-nav__link> <span class=md-ellipsis> is_number_float </span> </a> </li> <li class=md-nav__item> <a href=../is_number_integer/ class=md-nav__link> <span class=md-ellipsis> is_number_integer </span> </a> </li> <li class=md-nav__item> <a href=../is_number_unsigned/ class=md-nav__link> <span class=md-ellipsis> is_number_unsigned </span> </a> </li> <li class=md-nav__item> <a href=../is_object/ class=md-nav__link> <span class=md-ellipsis> is_object </span> </a> </li> <li class=md-nav__item> <a href=../is_primitive/ class=md-nav__link> <span class=md-ellipsis> is_primitive </span> </a> </li> <li class=md-nav__item> <a href=../is_string/ class=md-nav__link> <span class=md-ellipsis> is_string </span> </a> </li> <li class=md-nav__item> <a href=../is_structured/ class=md-nav__link> <span class=md-ellipsis> is_structured </span> </a> </li> <li class=md-nav__item> <a href=../items/ class=md-nav__link> <span class=md-ellipsis> items </span> </a> </li> <li class=md-nav__item> <a href=../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=../json_serializer/ class=md-nav__link> <span class=md-ellipsis> json_serializer </span> </a> </li> <li class=md-nav__item> <a href=../max_size/ class=md-nav__link> <span class=md-ellipsis> max_size </span> </a> </li> <li class=md-nav__item> <a href=../meta/ class=md-nav__link> <span class=md-ellipsis> meta </span> </a> </li> <li class=md-nav__item> <a href=../merge_patch/ class=md-nav__link> <span class=md-ellipsis> merge_patch </span> </a> </li> <li class=md-nav__item> <a href=../number_float_t/ class=md-nav__link> <span class=md-ellipsis> number_float_t </span> </a> </li> <li class=md-nav__item> <a href=../number_integer_t/ class=md-nav__link> <span class=md-ellipsis> number_integer_t </span> </a> </li> <li class=md-nav__item> <a href=../number_unsigned_t/ class=md-nav__link> <span class=md-ellipsis> number_unsigned_t </span> </a> </li> <li class=md-nav__item> <a href=../object/ class=md-nav__link> <span class=md-ellipsis> object </span> </a> </li> <li class=md-nav__item> <a href=../object_comparator_t/ class=md-nav__link> <span class=md-ellipsis> object_comparator_t </span> </a> </li> <li class=md-nav__item> <a href=../object_t/ class=md-nav__link> <span class=md-ellipsis> object_t </span> </a> </li> <li class=md-nav__item> <a href=../operator_ValueType/ class=md-nav__link> <span class=md-ellipsis> operator ValueType </span> </a> </li> <li class=md-nav__item> <a href=../operator_value_t/ class=md-nav__link> <span class=md-ellipsis> operator value_t </span> </a> </li> <li class=md-nav__item> <a href=../operator%5B%5D/ class=md-nav__link> <span class=md-ellipsis> operator[] </span> </a> </li> <li class=md-nav__item> <a href=../operator%3D/ class=md-nav__link> <span class=md-ellipsis> operator= </span> </a> </li> <li class=md-nav__item> <a href=../operator%2B%3D/ class=md-nav__link> <span class=md-ellipsis> operator+= </span> </a> </li> <li class=md-nav__item> <a href=../operator_eq/ class=md-nav__link> <span class=md-ellipsis> operator== </span> </a> </li> <li class=md-nav__item> <a href=../operator_ne/ class=md-nav__link> <span class=md-ellipsis> operator!= </span> </a> </li> <li class=md-nav__item> <a href=../operator_lt/ class=md-nav__link> <span class=md-ellipsis> operator< </span> </a> </li> <li class=md-nav__item> <a href=../operator_gt/ class=md-nav__link> <span class=md-ellipsis> operator> </span> </a> </li> <li class=md-nav__item> <a href=../operator_le/ class=md-nav__link> <span class=md-ellipsis> operator<= </span> </a> </li> <li class=md-nav__item> <a href=../operator_ge/ class=md-nav__link> <span class=md-ellipsis> operator>= </span> </a> </li> <li class=md-nav__item> <a href=../operator_spaceship/ class=md-nav__link> <span class=md-ellipsis> operator<=> </span> </a> </li> <li class=md-nav__item> <a href=../out_of_range/ class=md-nav__link> <span class=md-ellipsis> out_of_range </span> </a> </li> <li class=md-nav__item> <a href=../other_error/ class=md-nav__link> <span class=md-ellipsis> other_error </span> </a> </li> <li class=md-nav__item> <a href=../parse/ class=md-nav__link> <span class=md-ellipsis> parse </span> </a> </li> <li class=md-nav__item> <a href=../parse_error/ class=md-nav__link> <span class=md-ellipsis> parse_error </span> </a> </li> <li class=md-nav__item> <a href=../parse_event_t/ class=md-nav__link> <span class=md-ellipsis> parse_event_t </span> </a> </li> <li class=md-nav__item> <a href=../parser_callback_t/ class=md-nav__link> <span class=md-ellipsis> parser_callback_t </span> </a> </li> <li class=md-nav__item> <a href=../patch/ class=md-nav__link> <span class=md-ellipsis> patch </span> </a> </li> <li class=md-nav__item> <a href=../patch_inplace/ class=md-nav__link> <span class=md-ellipsis> patch_inplace </span> </a> </li> <li class=md-nav__item> <a href=../push_back/ class=md-nav__link> <span class=md-ellipsis> push_back </span> </a> </li> <li class=md-nav__item> <a href=../rbegin/ class=md-nav__link> <span class=md-ellipsis> rbegin </span> </a> </li> <li class=md-nav__item> <a href=../rend/ class=md-nav__link> <span class=md-ellipsis> rend </span> </a> </li> <li class=md-nav__item> <a href=../sax_parse/ class=md-nav__link> <span class=md-ellipsis> sax_parse </span> </a> </li> <li class=md-nav__item> <a href=../size/ class=md-nav__link> <span class=md-ellipsis> size </span> </a> </li> <li class=md-nav__item> <a href=../start_pos/ class=md-nav__link> <span class=md-ellipsis> start_pos </span> </a> </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> string_t </span> <span class="md-nav__icon md-icon"></span> </label> <a href=./ class="md-nav__link md-nav__link--active"> <span class=md-ellipsis> string_t </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=#template-parameters class=md-nav__link> <span class=md-ellipsis> Template parameters </span> </a> </li> <li class=md-nav__item> <a href=#notes class=md-nav__link> <span class=md-ellipsis> Notes </span> </a> <nav class=md-nav aria-label=Notes> <ul class=md-nav__list> <li class=md-nav__item> <a href=#default-type class=md-nav__link> <span class=md-ellipsis> Default type </span> </a> </li> <li class=md-nav__item> <a href=#encoding class=md-nav__link> <span class=md-ellipsis> Encoding </span> </a> </li> <li class=md-nav__item> <a href=#string-comparison class=md-nav__link> <span class=md-ellipsis> String comparison </span> </a> </li> <li class=md-nav__item> <a href=#storage class=md-nav__link> <span class=md-ellipsis> Storage </span> </a> </li> <li class=md-nav__item> <a href=#cross-basic_json-conversion-requirements class=md-nav__link> <span class=md-ellipsis> Cross-basic_json conversion requirements </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=#examples class=md-nav__link> <span class=md-ellipsis> Examples </span> </a> </li> <li class=md-nav__item> <a href=#version-history class=md-nav__link> <span class=md-ellipsis> Version history </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../swap/ class=md-nav__link> <span class=md-ellipsis> swap </span> </a> </li> <li class=md-nav__item> <a href=../std_swap/ class=md-nav__link> <span class=md-ellipsis> std::swap&lt;basic_json&gt; </span> </a> </li> <li class=md-nav__item> <a href=../to_bjdata/ class=md-nav__link> <span class=md-ellipsis> to_bjdata </span> </a> </li> <li class=md-nav__item> <a href=../to_bson/ class=md-nav__link> <span class=md-ellipsis> to_bson </span> </a> </li> <li class=md-nav__item> <a href=../to_cbor/ class=md-nav__link> <span class=md-ellipsis> to_cbor </span> </a> </li> <li class=md-nav__item> <a href=../to_msgpack/ class=md-nav__link> <span class=md-ellipsis> to_msgpack </span> </a> </li> <li class=md-nav__item> <a href=../to_string/ class=md-nav__link> <span class=md-ellipsis> to_string </span> </a> </li> <li class=md-nav__item> <a href=../to_ubjson/ class=md-nav__link> <span class=md-ellipsis> to_ubjson </span> </a> </li> <li class=md-nav__item> <a href=../type/ class=md-nav__link> <span class=md-ellipsis> type </span> </a> </li> <li class=md-nav__item> <a href=../type_error/ class=md-nav__link> <span class=md-ellipsis> type_error </span> </a> </li> <li class=md-nav__item> <a href=../type_name/ class=md-nav__link> <span class=md-ellipsis> type_name </span> </a> </li> <li class=md-nav__item> <a href=../unflatten/ class=md-nav__link> <span class=md-ellipsis> unflatten </span> </a> </li> <li class=md-nav__item> <a href=../update/ class=md-nav__link> <span class=md-ellipsis> update </span> </a> </li> <li class=md-nav__item> <a href=../value/ class=md-nav__link> <span class=md-ellipsis> value </span> </a> </li> <li class=md-nav__item> <a href=../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=../../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=../../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=../../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=../../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=../../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=../../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=../../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=../../adl_serializer/from_json/ class=md-nav__link> <span class=md-ellipsis> from_json </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../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=../../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=../../json_pointer/json_pointer/ class=md-nav__link> <span class=md-ellipsis> (Constructor) </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/back/ class=md-nav__link> <span class=md-ellipsis> back </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/empty/ class=md-nav__link> <span class=md-ellipsis> empty </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/front/ class=md-nav__link> <span class=md-ellipsis> front </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../json_pointer/operator_eq/ class=md-nav__link> <span class=md-ellipsis> operator== </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/operator_ne/ class=md-nav__link> <span class=md-ellipsis> operator!= </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/operator_slash/ class=md-nav__link> <span class=md-ellipsis> operator/ </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/operator_slasheq/ class=md-nav__link> <span class=md-ellipsis> operator/= </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/parent_pointer/ class=md-nav__link> <span class=md-ellipsis> parent_pointer </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/pop_back/ class=md-nav__link> <span class=md-ellipsis> pop_back </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/pop_front/ class=md-nav__link> <span class=md-ellipsis> pop_front </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/push_back/ class=md-nav__link> <span class=md-ellipsis> push_back </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/push_front/ class=md-nav__link> <span class=md-ellipsis> push_front </span> </a> </li> <li class=md-nav__item> <a href=../../json_pointer/string_t/ class=md-nav__link> <span class=md-ellipsis> string_t </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../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=../../json_sax/binary/ class=md-nav__link> <span class=md-ellipsis> binary </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/boolean/ class=md-nav__link> <span class=md-ellipsis> boolean </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/end_array/ class=md-nav__link> <span class=md-ellipsis> end_array </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/end_object/ class=md-nav__link> <span class=md-ellipsis> end_object </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/key/ class=md-nav__link> <span class=md-ellipsis> key </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/null/ class=md-nav__link> <span class=md-ellipsis> null </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/number_float/ class=md-nav__link> <span class=md-ellipsis> number_float </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/number_integer/ class=md-nav__link> <span class=md-ellipsis> number_integer </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/number_unsigned/ class=md-nav__link> <span class=md-ellipsis> number_unsigned </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/parse_error/ class=md-nav__link> <span class=md-ellipsis> parse_error </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/start_array/ class=md-nav__link> <span class=md-ellipsis> start_array </span> </a> </li> <li class=md-nav__item> <a href=../../json_sax/start_object/ class=md-nav__link> <span class=md-ellipsis> start_object </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../operator_ltlt/ class=md-nav__link> <span class=md-ellipsis> operator<<(basic_json), operator<<(json_pointer) </span> </a> </li> <li class=md-nav__item> <a href=../../operator_gtgt/ class=md-nav__link> <span class=md-ellipsis> operator>>(basic_json) </span> </a> </li> <li class=md-nav__item> <a href=../../operator_literal_json/ class=md-nav__link> <span class=md-ellipsis> operator""_json </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../ordered_json/ class=md-nav__link> <span class=md-ellipsis> ordered_json </span> </a> </li> <li class=md-nav__item> <a href=../../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_13> <div class="md-nav__link md-nav__container"> <a href=../../macros/ class="md-nav__link "> <span class=md-ellipsis> macros </span> </a> <label class="md-nav__link " for=__nav_4_13 id=__nav_4_13_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_13_label aria-expanded=false> <label class=md-nav__title for=__nav_4_13> <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=../../macros/json_assert/ class=md-nav__link> <span class=md-ellipsis> JSON_ASSERT </span> </a> </li> <li class=md-nav__item> <a href=../../macros/json_brace_init_copy_semantics/ class=md-nav__link> <span class=md-ellipsis> JSON_BRACE_INIT_COPY_SEMANTICS </span> </a> </li> <li class=md-nav__item> <a href=../../macros/json_throw_user/ class=md-nav__link> <span class=md-ellipsis> JSON_CATCH_USER, JSON_THROW_USER, JSON_TRY_USER </span> </a> </li> <li class=md-nav__item> <a href=../../macros/json_diagnostics/ class=md-nav__link> <span class=md-ellipsis> JSON_DIAGNOSTICS </span> </a> </li> <li class=md-nav__item> <a href=../../macros/json_diagnostic_positions/ class=md-nav__link> <span class=md-ellipsis> JSON_DIAGNOSTIC_POSITIONS </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../macros/json_has_cpp_11/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_CPP_11, JSON_HAS_CPP_14, JSON_HAS_CPP_17, JSON_HAS_CPP_20 </span> </a> </li> <li class=md-nav__item> <a href=../../macros/json_has_filesystem/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_EXPERIMENTAL_FILESYSTEM, JSON_HAS_FILESYSTEM </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../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=../../macros/json_has_std_format/ class=md-nav__link> <span class=md-ellipsis> JSON_HAS_STD_FORMAT </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../macros/json_noexception/ class=md-nav__link> <span class=md-ellipsis> JSON_NOEXCEPTION </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../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=../../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=../../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=../../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=../../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=../../macros/nlohmann_define_derived_type/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE, NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_WITH_DEFAULT, NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_ONLY_SERIALIZE, NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE, NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_WITH_DEFAULT, NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_ONLY_SERIALIZE </span> </a> </li> <li class=md-nav__item> <a href=../../macros/nlohmann_define_type_intrusive/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_INTRUSIVE, NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_DEFAULT, NLOHMANN_DEFINE_TYPE_INTRUSIVE_ONLY_SERIALIZE </span> </a> </li> <li class=md-nav__item> <a href=../../macros/nlohmann_define_type_non_intrusive/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE, NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT, NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_ONLY_SERIALIZE </span> </a> </li> <li class=md-nav__item> <a href=../../macros/nlohmann_define_type_with_names/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_NAMES, NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_DEFAULT_WITH_NAMES, NLOHMANN_DEFINE_TYPE_INTRUSIVE_ONLY_SERIALIZE_WITH_NAMES, NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_NAMES, NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT_WITH_NAMES, NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_ONLY_SERIALIZE_WITH_NAMES, NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_WITH_NAMES, NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_WITH_DEFAULT_WITH_NAMES, NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_ONLY_SERIALIZE_WITH_NAMES, NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_WITH_NAMES, NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_WITH_DEFAULT_WITH_NAMES, NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_ONLY_SERIALIZE_WITH_NAMES </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../macros/nlohmann_json_namespace_begin/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_NAMESPACE_BEGIN, NLOHMANN_JSON_NAMESPACE_END </span> </a> </li> <li class=md-nav__item> <a href=../../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=../../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=../../macros/nlohmann_json_serialize_enum_strict/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_SERIALIZE_ENUM_STRICT </span> </a> </li> <li class=md-nav__item> <a href=../../macros/nlohmann_json_version_major/ class=md-nav__link> <span class=md-ellipsis> NLOHMANN_JSON_VERSION_MAJOR, NLOHMANN_JSON_VERSION_MINOR, NLOHMANN_JSON_VERSION_PATCH </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_5> <div class="md-nav__link md-nav__container"> <a href=../../../community/ class="md-nav__link "> <span class=md-ellipsis> Community </span> </a> <label class="md-nav__link " for=__nav_5 id=__nav_5_label tabindex=0> <span class="md-nav__icon md-icon"></span> </label> </div> <nav class=md-nav data-md-level=1 aria-labelledby=__nav_5_label aria-expanded=false> <label class=md-nav__title for=__nav_5> <span class="md-nav__icon md-icon"></span> Community </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../../community/code_of_conduct/ class=md-nav__link> <span class=md-ellipsis> Code of Conduct </span> </a> </li> <li class=md-nav__item> <a href=../../../community/contribution_guidelines/ class=md-nav__link> <span class=md-ellipsis> Contribution Guidelines </span> </a> </li> <li class=md-nav__item> <a href=../../../community/quality_assurance/ class=md-nav__link> <span class=md-ellipsis> Quality assurance </span> </a> </li> <li class=md-nav__item> <a href=../../../community/governance/ class=md-nav__link> <span class=md-ellipsis> Governance </span> </a> </li> <li class=md-nav__item> <a href=../../../community/security_policy/ class=md-nav__link> <span class=md-ellipsis> Security Policy </span> </a> </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=#template-parameters class=md-nav__link> <span class=md-ellipsis> Template parameters </span> </a> </li> <li class=md-nav__item> <a href=#notes class=md-nav__link> <span class=md-ellipsis> Notes </span> </a> <nav class=md-nav aria-label=Notes> <ul class=md-nav__list> <li class=md-nav__item> <a href=#default-type class=md-nav__link> <span class=md-ellipsis> Default type </span> </a> </li> <li class=md-nav__item> <a href=#encoding class=md-nav__link> <span class=md-ellipsis> Encoding </span> </a> </li> <li class=md-nav__item> <a href=#string-comparison class=md-nav__link> <span class=md-ellipsis> String comparison </span> </a> </li> <li class=md-nav__item> <a href=#storage class=md-nav__link> <span class=md-ellipsis> Storage </span> </a> </li> <li class=md-nav__item> <a href=#cross-basic_json-conversion-requirements class=md-nav__link> <span class=md-ellipsis> Cross-basic_json conversion requirements </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=#examples class=md-nav__link> <span class=md-ellipsis> Examples </span> </a> </li> <li class=md-nav__item> <a href=#version-history class=md-nav__link> <span class=md-ellipsis> Version history </span> </a> </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/api/basic_json/string_t.md" title="Edit this page" class="md-content__button md-icon" rel="edit"> <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/api/basic_json/string_t.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=nlohmannbasic_jsonstring_t><small>nlohmann::basic_json::</small>string_t<a class=headerlink href=#nlohmannbasic_jsonstring_t title="Permanent link">&para;</a></h1> <div class=highlight><pre><span></span><code><span class=k>using</span><span class=w> </span><span class=n>string_t</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>StringType</span><span class=p>;</span>
</code></pre></div> <p>The type used to store <abbr title="JavaScript Object Notation">JSON</abbr> strings.</p> <p><a href="https://tools.ietf.org/html/rfc8259"><abbr title="Request for Comments">RFC</abbr> 8259</a> describes <abbr title="JavaScript Object Notation">JSON</abbr> strings as follows:</p> <blockquote> <p>A string is a sequence of zero or more Unicode characters.</p> </blockquote> <p>To store strings in C++, a type is defined by the template parameter described below. Unicode values are split by the <abbr title="JavaScript Object Notation">JSON</abbr> class into byte-sized characters during deserialization.</p> <h2 id=template-parameters>Template parameters<a class=headerlink href=#template-parameters title="Permanent link">&para;</a></h2> <dl> <dt><code>StringType</code></dt> <dd> <p>the container to store strings (e.g., <code>std::string</code>). Note this container is used for keys/names in objects, see <a href=../object_t/ >object_t</a>.</p> <p><code>StringType</code> must have a <code>char</code>-compatible <code>value_type</code>: the library relies on <abbr title="Unicode Transformation Format">UTF</abbr>-8/<code>char</code>-based storage and processing internally, so <code>std::wstring</code>, <code>std::u16string</code>, and <code>std::u32string</code> are <strong>not</strong> valid choices for <code>StringType</code>. To work with wide-character data, convert it to/from <abbr title="Unicode Transformation Format">UTF</abbr>-8 at the boundary instead -- see the <abbr title="Frequently Asked Questions">FAQ</abbr>'s <a href=../../../home/faq/#wide-string-handling>wide string handling</a> section for a conversion recipe.</p> </dd> </dl> <h2 id=notes>Notes<a class=headerlink href=#notes title="Permanent link">&para;</a></h2> <h4 id=default-type>Default type<a class=headerlink href=#default-type title="Permanent link">&para;</a></h4> <p>With the default values for <code>StringType</code> (<code>std::string</code>), the default value for <code>string_t</code> is <code class=highlight><span class=n>std</span><span class=o>::</span><span class=n>string</span></code>.</p> <h4 id=encoding>Encoding<a class=headerlink href=#encoding title="Permanent link">&para;</a></h4> <p>Strings are stored in <abbr title="Unicode Transformation Format">UTF</abbr>-8 encoding. Therefore, functions like <code>std::string::size()</code> or <code>std::string::length()</code> return the number of bytes in the string rather than the number of characters or glyphs.</p> <h4 id=string-comparison>String comparison<a class=headerlink href=#string-comparison title="Permanent link">&para;</a></h4> <p><a href="https://tools.ietf.org/html/rfc8259"><abbr title="Request for Comments">RFC</abbr> 8259</a> states:</p> <blockquote> <p>Software implementations are typically required to test names of object members for equality. Implementations that transform the textual representation into sequences of Unicode code units and then perform the comparison numerically, code unit by code unit, are interoperable in the sense that implementations will agree in all cases on equality or inequality of two strings. For example, implementations that compare strings with escaped characters unconverted may incorrectly find that <code>"a\\b"</code> and <code>"a\u005Cb"</code> are not equal.</p> </blockquote> <p>This implementation is interoperable as it does compare strings code unit by code unit.</p> <h4 id=storage>Storage<a class=headerlink href=#storage title="Permanent link">&para;</a></h4> <p>String values are stored as pointers in a <code>basic_json</code> type. That is, for any access to string values, a pointer of type <code>string_t*</code> must be dereferenced.</p> <h4 id=cross-basic_json-conversion-requirements>Cross-<code>basic_json</code> conversion requirements<a class=headerlink href=#cross-basic_json-conversion-requirements title="Permanent link">&para;</a></h4> <p>When converting a string value from one <code>basic_json</code> specialization to another via the <a href=../basic_json/#overload-4>converting constructor</a>, the target <code>string_t</code> must be directly constructible from the source <code>basic_json</code>'s <code>string_t</code> type. If this requirement is not met, the conversion does not fail; instead, the string is silently converted as an array of character codes, which is incorrect. See <a href="https://github.com/nlohmann/json/issues/3425">issue #3425</a> for details and an example.</p> <h2 id=examples>Examples<a class=headerlink href=#examples title="Permanent link">&para;</a></h2> <details class=example> <summary>Example</summary> <p>The following code shows that <code>string_t</code> is by default, a typedef to <code class=highlight><span class=n>std</span><span class=o>::</span><span class=n>string</span></code>.</p> <div class=highlight><pre><span></span><code><span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;iostream&gt;</span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;iomanip&gt;</span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</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=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>boolalpha</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>is_same</span><span class=o>&lt;</span><span class=n>std</span><span class=o>::</span><span class=n>string</span><span class=p>,</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>string_t</span><span class=o>&gt;::</span><span class=n>value</span><span class=w> </span><span class=o>&lt;&lt;</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=p>}</span>
</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code><span class=kc>true</span>
</code></pre></div> </details> <h2 id=version-history>Version history<a class=headerlink href=#version-history title="Permanent link">&para;</a></h2> <ul> <li>Added in version 1.0.0.</li> </ul> <!-- https://squidfunk.github.io/mkdocs-material/reference/tooltips/#adding-a-glossary --> <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" title="July 10, 2026 14:11:41 UTC">July 10, 2026</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 &copy; 2013-2026 Niels Lohmann </div> </div> <div class=md-social> <a href="https://github.com/nlohmann" target="_blank" rel="noopener" title="github.com" class="md-social__link"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 512 512"><!-- Font Awesome Free 7.1.0 by @fontawesome - 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