mirror of
https://github.com/nlohmann/json.git
synced 2026-10-06 14:40:32 +00:00
Niels Lohmann
0adb7783a4
Give basic_json_view the read-only access functions of basic_json: operator[] and at() with keys and indices, front()/back(), find(), contains(), count(), begin()/end() and cbegin()/cend(), items() with structured bindings from C++17 on, and type_name(). Exceptions have the ids and messages of the const functions of basic_json. Where basic_json has undefined behavior the view answers safely: operator[] with a missing key or an out-of-range index returns a discarded view, and front()/back() of an empty container throw invalid_iterator.214. Objects are iterated in document order, and all members are visited; duplicate-key lookups find the first member (as yyjson and simdjson do), while parse(), materialize(), and the map conversions keep the last value, as parse() does. Keys of up to 16 bytes are compared with two overlapping loads. Add value conversions: get<T>()/get_to() for arithmetic types, bool, nullptr_t, strings (std::basic_string copied, string_view_t without a copy), BasicJsonType, views, std::vector, and maps with string keys; get_string() for the string without a copy; number_token() for the number exactly as written in the source; value() with keys and JSON pointers; and operator[]/at()/ contains() with JSON pointers. Everything else, including types with from_json(), goes through materialize() of that subtree. get<T>() of arithmetic types is inlined down to the conversion, so reading an integer needs no call. detail::json_pointer_access exposes a pointer's reference tokens to code outside basic_json. Signed-off-by: Niels Lohmann <mail@nlohmann.me>
Documentation
Generate documentation
Note on documentation: The source files contain links to the online documentation at https://json.nlohmann.me.
This URL provides the most recent documentation and also applies to previous versions. Documentation for deprecated
functions is not removed; instead, it is marked as deprecated.
If you want to view the documentation for a specific tag or commit hash, you can generate it locally as follows (example
using tag v3.10.2):
git clone https://github.com/nlohmann/json.git
cd json
git checkout v3.10.2
make install_venv serve -C docs/mkdocs
Open http://127.0.0.1:8000/ in your browser. Replace any URL in the source code that points to
https://json.nlohmann.me with http://127.0.0.1:8000 to view the documentation for the selected tag or commit hash.