Doc update: IntoRobj and TryFromRobj needs to refer to each other

extendr-macros/src/lib.rs

@@ -223,6 +223,10 @@ pub fn Rraw(item: TokenStream) -> TokenStream {
 /// # }
 /// # Ok::<(), extendr_api::Error>(())
 /// ```
+///
+/// See [`IntoRobj`] for converting arbitrary Rust types into R type by using
+/// R's list / `List`.
+///
 #[proc_macro_derive(TryFromRobj)]
 pub fn derive_try_from_robj(item: TokenStream) -> TokenStream {
     list_struct::derive_try_from_robj(item)
@@ -233,7 +237,11 @@ pub fn derive_try_from_robj(item: TokenStream) -> TokenStream {
 /// This allows the struct to be converted to a named list in R,
 /// where the list names correspond to the field names of the Rust struct.
 ///
+/// Note that the R list may contain more fields, than those corresponding
+/// to the Rust type.
+///
 /// # Examples
+///
 /// In the below example, `converted` contains an R list object with the same fields as the
 /// `Foo` struct.
 /// ```ignore
@@ -255,7 +263,13 @@ pub fn derive_try_from_robj(item: TokenStream) -> TokenStream {
 /// # }
 /// # Ok::<(), extendr_api::Error>(())
 /// ```
+///
+/// See [`TryFromRobj`] for a `derive`-macro in the other direction, i.e.
+/// instantiation of a rust type, by an R list with fields corresponding to
+/// said type.
+///
 /// # Details
+///
 /// Note, the `From<Struct> for Robj` behaviour is different from what is obtained by applying the standard `#[extendr]` macro
 /// to an `impl` block. The `#[extendr]` behaviour returns to R a **pointer** to Rust memory, and generates wrapper functions for calling
 /// Rust functions on that pointer. The implementation from `#[derive(IntoRobj)]` actually converts the Rust structure
@@ -286,7 +300,6 @@ pub fn derive_into_robj(item: TokenStream) -> TokenStream {
 /// assert_eq!(df[0], r!([0, 1]));
 /// assert_eq!(df[1], r!(["abc", "xyz"]));
 /// ```
-
 #[proc_macro_derive(IntoDataFrameRow)]
 pub fn derive_into_dataframe(item: TokenStream) -> TokenStream {
     dataframe::derive_into_dataframe(item)