@ -51,18 +51,25 @@ use std::fmt::Debug;
/// A type that can be accessed through a reference-like proxy.
///
/// An instance of a `Proxied` can be accessed
/// immutably via `Proxied::View` and mutably via `Proxied::Mut`.
/// An instance of a `Proxied` can be accessed immutably via `Proxied::View`.
///
/// All Protobuf field types implement `Proxied`.
pub trait Proxied {
/// The proxy type that provides shared access to a `T`, like a `&'msg T`.
///
/// Most code should use the type alias [`View`].
type View < ' msg > : ViewProxy < ' msg , Proxied = Self > + Copy + Send + SettableValue < Self >
type View < ' msg > : ViewProxy < ' msg , Proxied = Self > + Copy + Send
where
Self : ' msg ;
}
/// A type that can be be accessed through a reference-like proxy.
///
/// An instance of a `MutProxied` can be accessed mutably via `MutProxied::Mut`
/// and immutably via `MutProxied::View`.
///
/// `MutProxied` is implemented by message, map and repeated field types.
pub trait MutProxied : Proxied {
/// The proxy type that provides exclusive mutable access to a `T`, like a
/// `&'msg mut T`.
///
@ -83,7 +90,7 @@ pub type View<'msg, T> = <T as Proxied>::View<'msg>;
///
/// This is more concise than fully spelling the associated type.
#[ allow(dead_code) ]
pub type Mut < ' msg , T > = < T as Proxied > ::Mut < ' msg > ;
pub type Mut < ' msg , T > = < T as Mut Proxied> ::Mut < ' msg > ;
/// Declares conversion operations common to all views.
///
@ -147,7 +154,10 @@ pub trait ViewProxy<'msg>: 'msg + Sync + Unpin + Sized + Debug {
///
/// This trait is intentionally made non-object-safe to prevent a potential
/// future incompatible change.
pub trait MutProxy < ' msg > : ViewProxy < ' msg > {
pub trait MutProxy < ' msg > : ViewProxy < ' msg >
where
Self ::Proxied : MutProxied ,
{
/// Gets an immutable view of this field. This is shorthand for `as_view`.
///
/// This provides a shorter lifetime than `into_view` but can also be called
@ -211,7 +221,7 @@ pub trait MutProxy<'msg>: ViewProxy<'msg> {
///
/// All scalar and message types implement `ProxiedWithPresence`, while repeated
/// types don't.
pub trait ProxiedWithPresence : Proxied {
pub trait ProxiedWithPresence : Mut Proxied {
/// The data necessary to store a present field mutator proxying `Self`.
/// This is the contents of `PresentField<'msg, Self>`.
type PresentMutData < ' msg > : MutProxy < ' msg , Proxied = Self > ;
@ -233,7 +243,7 @@ pub trait ProxiedWithPresence: Proxied {
/// Values that can be used to set a field of `T`.
pub trait SettableValue < T > : Sized
where
T : Proxied + ? Sized ,
T : Mut Proxied + ? Sized ,
{
/// Consumes `self` to set the given mutator to the value of `self`.
#[ doc(hidden) ]
@ -308,6 +318,9 @@ mod tests {
impl Proxied for MyProxied {
type View < ' msg > = MyProxiedView < ' msg > ;
}
impl MutProxied for MyProxied {
type Mut < ' msg > = MyProxiedMut < ' msg > ;
}
@ -460,7 +473,7 @@ mod tests {
y : & ' b View < ' a , T > ,
) -> [ View < ' b , T > ; 2 ]
where
T : Proxied ,
T : Mut Proxied,
' a : ' b ,
{
// `[x, y]` fails to compile because `'a` is not the same as `'b` and the `View`
@ -509,7 +522,7 @@ mod tests {
fn reborrow_generic_mut_into_view < ' a , ' b , T > ( x : Mut < ' a , T > , y : View < ' b , T > ) -> [ View < ' b , T > ; 2 ]
where
T : Proxied ,
T : Mut Proxied,
' a : ' b ,
{
[ x . into_view ( ) , y ]
@ -529,7 +542,7 @@ mod tests {
fn reborrow_generic_mut_into_mut < ' a , ' b , T > ( x : Mut < ' a , T > , y : Mut < ' b , T > ) -> [ Mut < ' b , T > ; 2 ]
where
T : Proxied ,
T : Mut Proxied,
' a : ' b ,
{
// `[x, y]` fails to compile because `'a` is not the same as `'b` and the `Mut`