#[doc(hidden)]pub unsafe fn sidecar_r_struct<'a, T: TypedExternal>(x: SEXP) -> Ref<'a, T>Expand description
The live T of the external pointer x carries (sidecar_receiver),
borrowed shared, for the R getters of a struct field (a field that is not
a Sidecar). A pointer without an address is refused: with the classed
restored-object errors when T built it (refuse_restored), else as a
null pointer (refusal_message).
§Panics
When x carries no live external pointer to a T, or with the
miniextendr_borrow_conflict R error while a running call holds the value
mutably.
§Safety
Must be called from R’s main thread with a valid x; the borrow must end
while x keeps its value.