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Niels Lohmann
26b10a7b18
Every claim on the page was re-checked by compiling and running it, including the rows that say a type cannot be used, which were checked to fail for the documented reason and not merely to fail. Twenty-four claims were wrong. The most consequential: the incomplete-type constraint applies to ObjectType only. object_t is instantiated inside the class definition, because it is probed for key_compare; array_t is only named there and is not instantiated until basic_json is complete. So eastl::vector, QList and QVector are not excluded by incomplete types at all -- they simply have no max_size() -- and absl::InlinedVector is excluded for a subtler reason of its own. Further corrections: ObjectType does not need erase(key), which has a fallback, but does need at(key) for UBJSON output; only == and < are used, or == and <=> under C++20, not all six; the documented adapter does not fit ankerl or robin_hood. ArrayType needs no initializer-list insert, and value_type, the (count, value) constructor and swappability are per-function, not always. BinaryType needs a range insert for CBOR indefinite-length byte strings and does not need push_back. StringType needs append(const StringType&) unconditionally, and does not need operator!= or operator== against const char*; empty(), resize(n) and reserve(n) are per-subsystem; int_to_string is needed by diff, items and std::hash rather than by JSON Pointer or flatten. BooleanType must be implicitly convertible from bool, and JSONSerializer's second parameter need not carry a default. std::pmr::string was wrong in the other direction this time: a moved-in string does keep its memory resource, and later growth allocates from it. Only copies land on the default resource. Five requirement violations are not caught at compile time rather than the two the page claimed; they are now listed together up front. Split every compatibility table into what works and what does not, as the reasons in the second half are the useful part. Signed-off-by: Niels Lohmann <mail@nlohmann.me>