Want various convenience methods on netdoc argument encoder etc.
I think we want at least
impl ItemEncoder {
pub fn args(self, impl Iterator<Item=&dyn ItemArgument>) -> Self;
pub fn arg_base64(self, t: impl Writeable) -> Result<Self, tor_bytes::Error>;
}
// and maybe
impl Extend<impl ItemArgument> for ItemEncoder {..}
I also think we want something like
/// Helper that encodes a list of `T` as a count (of type `N`) followed by the encodings of the items, concatenated
pub struct tor_bytes::CountedList<N, T>(T, PhantomData<N>);
impl Writeable for CountedList<N, T> where T: ExactSizeIterator<impl Writeable> {..}
Prompted by reading !1070 (merged)