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Niels Lohmann
0b28c63bad
NLOHMANN_JSON_GET_MACRO resolves 64 positional arguments, with NAME at position 65. NLOHMANN_JSON_TYPE_TAG dispatches on Type plus the member list, so it resolves correctly up to the 63 members NLOHMANN_JSON_PASTE supports. NLOHMANN_JSON_DERIVED_TYPE_TAG dispatched on the two-token Type,BaseType prefix plus the member list, running out one slot early: at 63 members, position 65 landed on the last member name instead of a sentinel and NLOHMANN_JSON_CAT built an undefined identifier such as NLOHMANN_JSON_DEFINE_DERIVED_TYPE_INTRUSIVE_m63, with the compiler reporting "unknown type name 'm1'" once per member and nothing pointing at an argument-count limit. That silently reduced all six NLOHMANN_DEFINE_DERIVED_TYPE_* macros from 63 members to 62, contradicting the "up to 63 members" contract in docs/mkdocs/docs/api/macros/nlohmann_define_derived_type.md. Drop the leading Type and defer to NLOHMANN_JSON_TYPE_TAG so the tag is computed from BaseType plus the member list, which fits the available slots. The zero-own-member derived bodies are therefore selected by tag 1 rather than 2, and the sentinel table for the derived tag is no longer needed. Add a regression test at the documented maximum for both the plain and the derived macros; it fails to compile against the previous dispatch. Signed-off-by: Niels Lohmann <mail@nlohmann.me>