num::debug::sampling_compiled_in

Defined in header <core/debug.hpp>

constexpr bool sampling_compiled_in = NUMERICS_DIAGNOSTICS >= 2;

Whether property sampling exists in this build.

Guard a probe with if constexpr (!sampling_compiled_in) { return; } and its body is discarded rather than branched over. This is what makes preset::production remove the code, which the documentation claimed long before it was true.