Niels Lohmann 8220c48141 Read iterator pairs of std::string and std::vector as pointer ranges ...

Before C++20, a pair of iterators of a contiguous container cannot be told
from any other random-access iterator, so json::parse(s.begin(), s.end())
on a std::string or std::vector<char> was read one character at a time,
without the bulk scans of strings, numbers and indentation that the
container itself gets (the container overload of input_adapter() already
maps it to a pointer range). The iterators of std::string and of a
std::vector of 1-byte integral elements are now matched exactly and mapped
to the pointer range they cover; an empty range is not dereferenced. The
character type stays the same, so the results and error positions do not
change.

parse(first, last) of a std::string gets 1.7-2.0x as fast in C++17 on an
Apple M1 Max, accept(first, last) 2.7-3.1x, and from_cbor(first, last) of a
std::vector 8-23% faster.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

2026-11-06 06:47:12 +01:00

..

json_fwd.hpp

json_view: one SIMD macro set with the library (#5921)

2026-10-26 20:13:31 +01:00

json_literals.hpp

Move the user-defined string literals to <nlohmann/json_literals.hpp> and add JSON_NO_AUTOMATIC_UDLS (#5610)

2026-09-30 20:08:17 +02:00

json_view.hpp

Fix the MSVC and GCC builds of develop (C4127, -Weffc++) (#6016)

2026-11-02 20:07:00 +01:00

json.hpp

Read iterator pairs of std::string and std::vector as pointer ranges

2026-11-06 06:47:12 +01:00