object-introspection/types/std_variant.toml

[info]
typeName = "std::variant"
ctype = "STD_VARIANT_TYPE"
header = "variant"
ns = ["namespace std"]

[codegen]
decl = """
template<class... Types>
void getSizeType(const %1%<Types...> &container, size_t& returnArg);
"""

func = """
template<class... Types>
void getSizeType(const %1%<Types...> &container, size_t& returnArg)
{
  SAVE_SIZE(sizeof(%1%<Types...>));
  SAVE_DATA(container.index());

  // This check should be `container.valueless_by_exception()` but it doesn't
  // work with the variable sized integers used in `std::variant`. For fewer
  // than 256 options it uses a `uint8_t` index but checks against -1 of
  // `uintptr_t`. Manually check for any out of bounds indices as a workaround.
  if (container.index() >= sizeof...(Types)) {
    return;
  }

  std::visit([&returnArg](auto &&arg) {
    // Account for inline contents
    SAVE_SIZE(-sizeof(arg));
    getSizeType(arg, returnArg);
  }, container);
}
"""