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Niels LohmannandClaude
da42a627dc
* Stop dump() from heap-allocating its output adapter per call The serializer held its output sink as output_adapter_t<char> (a std::shared_ptr<output_adapter_protocol<char>>), which dump() and operator<< built via make_shared -- one heap allocation per call for a sink that only wraps a reference to the caller's string or stream. Hold the sink as a non-owning output_adapter_protocol<char>* instead and construct the concrete adapter on the stack at the call site. The write path (o->write_characters) is unchanged, so output is byte-for-byte identical; a compact dump() of a small object drops from 2 heap allocations to 1 (only the returned string remains), ~3% faster. Completes the per-call allocation cleanup on this branch, which already removed the indent_string buffer (both were reported in #5413). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01L1oJ2ggRHS37zeVe94QTA1 Signed-off-by: Claude <noreply@anthropic.com> * Take the output adapter by reference at the serializer ctor Per review: the serializer still holds the adapter as a non-owning pointer, but the constructor now takes output_adapter_protocol<char>& and takes its address internally, so every call site passes a reference. A reference cannot be null and reads as a borrow, which makes the lifetime contract harder to get wrong than handing over a raw pointer. The stored member and the write path are unchanged. Co-Authored-By: Claude <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01XAYM1qhSA2FDaDcGfPW3fG Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Claude <noreply@anthropic.com> Signed-off-by: Niels Lohmann <mail@nlohmann.me> Co-authored-by: Claude <noreply@anthropic.com>