Niels Lohmann ba25f96169 Reserve the storage of an ordered_json in flatten() once ...

flatten() appended the entries to an ordered_map one by one, so its vector
grew by doubling and moved every entry about once in total. The number of
entries is known after a walk over the value that only counts (it needs no
path strings), so objects with a reserve() are given that capacity first.
std::map has no reserve() and is unchanged.

flatten() of an ordered_json (instructions on macOS, Linux Ir GCC 13 / Clang 18):
citm_catalog 36.8M -> 23.1M, 32.7M -> 17.1M / 31.7M -> 16.8M; twitter 20.5M ->
13.6M, 17.6M -> 10.0M / 17.0M -> 9.8M. Output is identical.

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

2026-10-22 09:29:49 +02:00

..

conversions

Use standard library helpers where available, with C++11 fallbacks (#5876)

2026-10-21 20:14:59 +02:00

input

Use standard library helpers where available, with C++11 fallbacks (#5876)

2026-10-21 20:14:59 +02:00

iterators

Fix CI failures on develop from the API performance stack (#5860)

2026-10-16 19:16:21 +02:00

meta

Use standard library helpers where available, with C++11 fallbacks (#5876)

2026-10-21 20:14:59 +02:00

output

Use standard library helpers where available, with C++11 fallbacks (#5876)

2026-10-21 20:14:59 +02:00

view

Use standard library helpers where available, with C++11 fallbacks (#5876)

2026-10-21 20:14:59 +02:00

abi_config.hpp

Add json_document and json_view: node index, parser, and document (#5620)

2026-10-21 10:21:27 +02:00

abi_macros.hpp

Scan strings with SSE2, SSSE3, or NEON (#5853)

2026-10-21 20:00:50 +02:00

bit_ops.hpp

Use standard library helpers where available, with C++11 fallbacks (#5876)

2026-10-21 20:14:59 +02:00

exceptions.hpp

Fix CI failures on develop from the API performance stack (#5860)

2026-10-16 19:16:21 +02:00

hash.hpp

Make std::hash<basic_json> consistent with operator== for numbers (#5772)

2026-10-07 19:18:51 +02:00

json_custom_base_class.hpp

Fix ADL leak of nlohmann::detail through basic_json's default base class (#5238)

2026-07-06 12:47:24 +02:00

json_pointer.hpp

Reserve the storage of an ordered_json in flatten() once

2026-10-22 09:29:49 +02:00

json_ref.hpp

Copy a pair-shaped array value under JSON_BRACE_INIT_COPY_SEMANTICS (#5701)

2026-10-07 07:39:05 +02:00

macro_scope.hpp

Silence macro-to-enum for the endianness macros (#5881)

2026-10-22 08:40:05 +02:00

macro_unscope.hpp

Use standard library helpers where available, with C++11 fallbacks (#5876)

2026-10-21 20:14:59 +02:00

recursion_depth_limit.hpp

Share one nesting depth limit between all bounded descents (#5637)

2026-09-30 20:06:43 +02:00

string_concat.hpp

Deduplicate basic_json internals; make insert(pos, json&&) move (#5727)

2026-10-04 11:57:41 +02:00

string_escape.hpp

Fix compiler warnings on develop from the API performance stack (#5858)

2026-10-15 22:42:46 +02:00

string_utils.hpp

Make UTF8_ACCEPT/UTF8_REJECT inline variables to avoid TU-local exposure in modules (#5797)

2026-10-09 23:38:42 +02:00

value_t.hpp

Fix silent wrong results for custom number types (#5805)

2026-10-21 08:36:31 +00:00