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json/docs
Niels LohmannandClaude Opus 5 06feaa8d04 docs: list the types that are known to work for each template parameter
Follow up on the template parameter requirements page: state, for every
template parameter, which concrete types work and where they stop working.
Each entry was verified by compiling and running a common workload (DOM
access, dump, parse, CBOR/MessagePack round-trip, flatten, hash) against that
instantiation.

Findings worth calling out:

- ObjectType no longer needs a key_compare member type, so the std::unordered_map
  adapter only has to restore the template argument order. A hash-ordered
  ObjectType works everywhere except unflatten(), which reconstructs an array
  only when it meets the reference token 0 before the other indices.
- ArrayType: std::deque works when wrapped to add capacity(); std::list does not.
- StringType: std::pmr::string and std::basic_string with a custom allocator
  compile for the DOM, dump, and parse, but not for the binary readers, flatten,
  or diff, because the library assigns std::string values to string_t and
  int_to_string cannot be overloaded for a type in namespace std.
- NumberFloatType: long double works for dump and parse but not for the binary
  formats, which have no encoding for it.
- BinaryType: std::vector<std::byte> supports assignment, get, and the binary
  formats, but neither dump nor std::hash<basic_json>.

Also record the object_comparator_t fix in its version history.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018hxZxz8svM54c6ATEvXp5E
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-08-28 17:38:55 +00:00
..
2025-04-11 10:41:14 +02:00
2025-04-11 10:41:14 +02:00

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