Module dump_cpp 

The value-printing code the Fast DDS probe needs to answer with.

dump.rs writes C, for the two generators whose output is a plain struct. Fast DDS generates a C++ class, so every member is read through its getter and the expressions have a shape of their own — the same split fill.rs and fill_cpp.rs have in the other direction.

sample.x                       // Cyclone, RTI
sample.x()                     // Fast DDS
sample.location.x              // Cyclone, RTI
sample.location().x()          // Fast DDS

Why this is not a self-oracle

The statements read the vendor’s object, which the vendor’s deserialiser filled. A printer that read the wrong member shows up as a disagreement between the implementations, never as a false agreement.

What the C++ binding has that the C one does not

Three constructs dump.rs refuses are printable here, because the C++ mapping does define them: a bitset is a struct of public C++ bit-fields, a map is a std::map, and a wstring is a std::wstring whose element is wchar_t. Only fixed<P, S> stays refused, and there because fastddsgen rejects it in the IDL before any accessor exists to read.

Functions

dump_fastdds

Emit the C++ statements that print sample as canonical JSON.