20 trace_base(trace_base
const &) =
delete;
21 trace_base(trace_base &&) =
delete;
22 trace_base &operator=(trace_base
const &) =
delete;
23 trace_base &operator=(trace_base &&) =
delete;
32 virtual void log()
const noexcept = 0;
35 inline static thread_local trace_base *_top =
nullptr;
38 trace_base *_next =
nullptr;