Core encoding and decoding interfaces.
*/
-use std::any;
use std::borrow::Cow;
use std::cell::{Cell, RefCell};
use std::marker::PhantomData;
fn error(&mut self, err: &str) -> Self::Error;
}
-pub trait Encodable {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error>;
-}
-
-pub trait Decodable: Sized {
- fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error>;
-}
-
-impl Encodable for usize {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_usize(*self)
- }
-}
-
-impl Decodable for usize {
- fn decode<D: Decoder>(d: &mut D) -> Result<usize, D::Error> {
- d.read_usize()
- }
-}
-
-impl Encodable for u8 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_u8(*self)
- }
-}
-
-impl Decodable for u8 {
- fn decode<D: Decoder>(d: &mut D) -> Result<u8, D::Error> {
- d.read_u8()
- }
-}
-
-impl Encodable for u16 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_u16(*self)
- }
-}
-
-impl Decodable for u16 {
- fn decode<D: Decoder>(d: &mut D) -> Result<u16, D::Error> {
- d.read_u16()
- }
-}
-
-impl Encodable for u32 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_u32(*self)
- }
+/// Trait for types that can be serialized
+///
+/// This can be implemented using the `Encodable`, `TyEncodable` and
+/// `MetadataEncodable` macros.
+///
+/// * `Encodable` should be used in crates that don't depend on
+/// `rustc_middle`.
+/// * `MetadataEncodable` is used in `rustc_metadata` for types that contain
+/// `rustc_metadata::rmeta::Lazy`.
+/// * `TyEncodable` should be used for types that are only serialized in crate
+/// metadata or the incremental cache. This is most types in `rustc_middle`.
+pub trait Encodable<S: Encoder> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error>;
}
-impl Decodable for u32 {
- fn decode<D: Decoder>(d: &mut D) -> Result<u32, D::Error> {
- d.read_u32()
- }
-}
+/// Trait for types that can be deserialized
+///
+/// This can be implemented using the `Decodable`, `TyDecodable` and
+/// `MetadataDecodable` macros.
+///
+/// * `Decodable` should be used in crates that don't depend on
+/// `rustc_middle`.
+/// * `MetadataDecodable` is used in `rustc_metadata` for types that contain
+/// `rustc_metadata::rmeta::Lazy`.
+/// * `TyDecodable` should be used for types that are only serialized in crate
+/// metadata or the incremental cache. This is most types in `rustc_middle`.
+pub trait Decodable<D: Decoder>: Sized {
+ fn decode(d: &mut D) -> Result<Self, D::Error>;
+}
+
+macro_rules! direct_serialize_impls {
+ ($($ty:ident $emit_method:ident $read_method:ident),*) => {
+ $(
+ impl<S: Encoder> Encodable<S> for $ty {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
+ s.$emit_method(*self)
+ }
+ }
-impl Encodable for ::std::num::NonZeroU32 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+ impl<D: Decoder> Decodable<D> for $ty {
+ fn decode(d: &mut D) -> Result<$ty, D::Error> {
+ d.$read_method()
+ }
+ }
+ )*
+ }
+}
+
+direct_serialize_impls! {
+ usize emit_usize read_usize,
+ u8 emit_u8 read_u8,
+ u16 emit_u16 read_u16,
+ u32 emit_u32 read_u32,
+ u64 emit_u64 read_u64,
+ u128 emit_u128 read_u128,
+ isize emit_isize read_isize,
+ i8 emit_i8 read_i8,
+ i16 emit_i16 read_i16,
+ i32 emit_i32 read_i32,
+ i64 emit_i64 read_i64,
+ i128 emit_i128 read_i128,
+ f32 emit_f32 read_f32,
+ f64 emit_f64 read_f64,
+ bool emit_bool read_bool,
+ char emit_char read_char
+}
+
+impl<S: Encoder> Encodable<S> for ::std::num::NonZeroU32 {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_u32(self.get())
}
}
-impl Decodable for ::std::num::NonZeroU32 {
- fn decode<D: Decoder>(d: &mut D) -> Result<Self, D::Error> {
+impl<D: Decoder> Decodable<D> for ::std::num::NonZeroU32 {
+ fn decode(d: &mut D) -> Result<Self, D::Error> {
d.read_u32().map(|d| ::std::num::NonZeroU32::new(d).unwrap())
}
}
-impl Encodable for u64 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_u64(*self)
- }
-}
-
-impl Decodable for u64 {
- fn decode<D: Decoder>(d: &mut D) -> Result<u64, D::Error> {
- d.read_u64()
- }
-}
-
-impl Encodable for u128 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_u128(*self)
- }
-}
-
-impl Decodable for u128 {
- fn decode<D: Decoder>(d: &mut D) -> Result<u128, D::Error> {
- d.read_u128()
- }
-}
-
-impl Encodable for isize {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_isize(*self)
- }
-}
-
-impl Decodable for isize {
- fn decode<D: Decoder>(d: &mut D) -> Result<isize, D::Error> {
- d.read_isize()
- }
-}
-
-impl Encodable for i8 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_i8(*self)
- }
-}
-
-impl Decodable for i8 {
- fn decode<D: Decoder>(d: &mut D) -> Result<i8, D::Error> {
- d.read_i8()
- }
-}
-
-impl Encodable for i16 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_i16(*self)
- }
-}
-
-impl Decodable for i16 {
- fn decode<D: Decoder>(d: &mut D) -> Result<i16, D::Error> {
- d.read_i16()
- }
-}
-
-impl Encodable for i32 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_i32(*self)
- }
-}
-
-impl Decodable for i32 {
- fn decode<D: Decoder>(d: &mut D) -> Result<i32, D::Error> {
- d.read_i32()
- }
-}
-
-impl Encodable for i64 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_i64(*self)
- }
-}
-
-impl Decodable for i64 {
- fn decode<D: Decoder>(d: &mut D) -> Result<i64, D::Error> {
- d.read_i64()
- }
-}
-
-impl Encodable for i128 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_i128(*self)
- }
-}
-
-impl Decodable for i128 {
- fn decode<D: Decoder>(d: &mut D) -> Result<i128, D::Error> {
- d.read_i128()
+impl<S: Encoder> Encodable<S> for str {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
+ s.emit_str(self)
}
}
-impl Encodable for str {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder> Encodable<S> for &str {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_str(self)
}
}
-impl Encodable for String {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder> Encodable<S> for String {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_str(&self[..])
}
}
-impl Decodable for String {
- fn decode<D: Decoder>(d: &mut D) -> Result<String, D::Error> {
+impl<D: Decoder> Decodable<D> for String {
+ fn decode(d: &mut D) -> Result<String, D::Error> {
Ok(d.read_str()?.into_owned())
}
}
-impl Encodable for f32 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_f32(*self)
- }
-}
-
-impl Decodable for f32 {
- fn decode<D: Decoder>(d: &mut D) -> Result<f32, D::Error> {
- d.read_f32()
- }
-}
-
-impl Encodable for f64 {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_f64(*self)
- }
-}
-
-impl Decodable for f64 {
- fn decode<D: Decoder>(d: &mut D) -> Result<f64, D::Error> {
- d.read_f64()
- }
-}
-
-impl Encodable for bool {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_bool(*self)
- }
-}
-
-impl Decodable for bool {
- fn decode<D: Decoder>(d: &mut D) -> Result<bool, D::Error> {
- d.read_bool()
- }
-}
-
-impl Encodable for char {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- s.emit_char(*self)
- }
-}
-
-impl Decodable for char {
- fn decode<D: Decoder>(d: &mut D) -> Result<char, D::Error> {
- d.read_char()
- }
-}
-
-impl Encodable for () {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder> Encodable<S> for () {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_unit()
}
}
-impl Decodable for () {
- fn decode<D: Decoder>(d: &mut D) -> Result<(), D::Error> {
+impl<D: Decoder> Decodable<D> for () {
+ fn decode(d: &mut D) -> Result<(), D::Error> {
d.read_nil()
}
}
-impl<T> Encodable for PhantomData<T> {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T> Encodable<S> for PhantomData<T> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_unit()
}
}
-impl<T> Decodable for PhantomData<T> {
- fn decode
<D: Decoder>(d: &mut D) -> Result<PhantomData<T>, D::Error> {
+impl<D: Decoder, T> Decodable<D> for PhantomData<T> {
+ fn decode(d: &mut D) -> Result<PhantomData<T>, D::Error> {
d.read_nil()?;
Ok(PhantomData)
}
}
-impl<T: Decodable> Decodable for Box<[T]> {
- fn decode<D: Decoder>(d: &mut D) -> Result<Box<[T]>, D::Error> {
+impl<D: Decoder, T: Decodable<D>> Decodable<D> for Box<[T]> {
+ fn decode(d: &mut D) -> Result<Box<[T]>, D::Error> {
let v: Vec<T> = Decodable::decode(d)?;
Ok(v.into_boxed_slice())
}
}
-impl<T: Encodable> Encodable for Rc<T> {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T: Encodable<S>> Encodable<S> for Rc<T> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
(**self).encode(s)
}
}
-impl<T: Decodable> Decodable for Rc<T> {
- fn decode<D: Decoder>(d: &mut D) -> Result<Rc<T>, D::Error> {
+impl<D: Decoder, T: Decodable<D>> Decodable<D> for Rc<T> {
+ fn decode(d: &mut D) -> Result<Rc<T>, D::Error> {
Ok(Rc::new(Decodable::decode(d)?))
}
}
-impl<T: Encodable> Encodable for [T] {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T: Encodable<S>> Encodable<S> for [T] {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_seq(self.len(), |s| {
for (i, e) in self.iter().enumerate() {
s.emit_seq_elt(i, |s| e.encode(s))?
}
}
-impl<T: Encodable> Encodable for Vec<T> {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T: Encodable<S>> Encodable<S> for Vec<T> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_seq(self.len(), |s| {
for (i, e) in self.iter().enumerate() {
s.emit_seq_elt(i, |s| e.encode(s))?
}
}
-impl<T: Decodable> Decodable for Vec<T> {
- fn decode<D: Decoder>(d: &mut D) -> Result<Vec<T>, D::Error> {
+impl<D: Decoder, T: Decodable<D>> Decodable<D> for Vec<T> {
+ fn decode(d: &mut D) -> Result<Vec<T>, D::Error> {
d.read_seq(|d, len| {
let mut v = Vec::with_capacity(len);
for i in 0..len {
}
}
-impl Encodable for [u8; 20] {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder> Encodable<S> for [u8; 20] {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_seq(self.len(), |s| {
for (i, e) in self.iter().enumerate() {
s.emit_seq_elt(i, |s| e.encode(s))?
}
}
-impl Decodable for [u8; 20] {
- fn decode<D: Decoder>(d: &mut D) -> Result<[u8; 20], D::Error> {
+impl<D: Decoder> Decodable<D> for [u8; 20] {
+ fn decode(d: &mut D) -> Result<[u8; 20], D::Error> {
d.read_seq(|d, len| {
assert!(len == 20);
let mut v = [0u8; 20];
}
}
-impl<'a, T: Encodable> Encodable for Cow<'a, [T]>
+impl<'a, S: Encoder, T: Encodable<S>> Encodable<S> for Cow<'a, [T]>
where
[T]: ToOwned<Owned = Vec<T>>,
{
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_seq(self.len(), |s| {
for (i, e) in self.iter().enumerate() {
s.emit_seq_elt(i, |s| e.encode(s))?
}
}
-impl<T: Decodable + ToOwned> Decodable for Cow<'static, [T]>
+impl<D: Decoder, T: Decodable<D> + ToOwned> Decodable<D> for Cow<'static, [T]>
where
[T]: ToOwned<Owned = Vec<T>>,
{
- fn decode<D: Decoder>(d: &mut D) -> Result<Cow<'static, [T]>, D::Error> {
+ fn decode(d: &mut D) -> Result<Cow<'static, [T]>, D::Error> {
d.read_seq(|d, len| {
let mut v = Vec::with_capacity(len);
for i in 0..len {
}
}
-impl<T: Encodable> Encodable for Option<T> {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T: Encodable<S>> Encodable<S> for Option<T> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_option(|s| match *self {
None => s.emit_option_none(),
Some(ref v) => s.emit_option_some(|s| v.encode(s)),
}
}
-impl<T: Decodable> Decodable for Option<T> {
- fn decode<D: Decoder>(d: &mut D) -> Result<Option<T>, D::Error> {
+impl<D: Decoder, T: Decodable<D>> Decodable<D> for Option<T> {
+ fn decode(d: &mut D) -> Result<Option<T>, D::Error> {
d.read_option(|d, b| if b { Ok(Some(Decodable::decode(d)?)) } else { Ok(None) })
}
}
-impl<T1: Encodable, T2: Encodable> Encodable for Result<T1, T2> {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T1: Encodable<S>, T2: Encodable<S>> Encodable<S> for Result<T1, T2> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
s.emit_enum("Result", |s| match *self {
Ok(ref v) => {
s.emit_enum_variant("Ok", 0, 1, |s| s.emit_enum_variant_arg(0, |s| v.encode(s)))
}
}
-impl<T1: Decodable, T2: Decodable> Decodable for Result<T1, T2> {
- fn decode<D: Decoder>(d: &mut D) -> Result<Result<T1, T2>, D::Error> {
+impl<D: Decoder, T1: Decodable<D>, T2: Decodable<D>> Decodable<D> for Result<T1, T2> {
+ fn decode(d: &mut D) -> Result<Result<T1, T2>, D::Error> {
d.read_enum("Result", |d| {
d.read_enum_variant(&["Ok", "Err"], |d, disr| match disr {
0 => Ok(Ok(d.read_enum_variant_arg(0, |d| T1::decode(d))?)),
macro_rules! tuple {
() => ();
( $($name:ident,)+ ) => (
- impl<$($name:Decodable),+> Decodable for ($($name,)+) {
+ impl<D: Decoder, $($name: Decodable<D>),+> Decodable<D> for ($($name,)+) {
#[allow(non_snake_case)]
- fn decode<D: Decoder>(d: &mut D) -> Result<($($name,)+), D::Error> {
+ fn decode(d: &mut D) -> Result<($($name,)+), D::Error> {
let len: usize = count!($($name)+);
d.read_tuple(len, |d| {
let mut i = 0;
})
}
}
- impl<$($name:Encodable),+> Encodable for ($($name,)+) {
+ impl<S: Encoder, $($name: Encodable<S>),+> Encodable<S> for ($($name,)+) {
#[allow(non_snake_case)]
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
let ($(ref $name,)+) = *self;
let mut n = 0;
$(let $name = $name; n += 1;)+
tuple! { T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, }
-impl Encodable for path::Path {
- fn encode<S: Encoder>(&self, e: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder> Encodable<S> for path::Path {
+ fn encode(&self, e: &mut S) -> Result<(), S::Error> {
self.to_str().unwrap().encode(e)
}
}
-impl Encodable for path::PathBuf {
- fn encode<S: Encoder>(&self, e: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder> Encodable<S> for path::PathBuf {
+ fn encode(&self, e: &mut S) -> Result<(), S::Error> {
path::Path::encode(self, e)
}
}
-impl Decodable for path::PathBuf {
- fn decode
<D: Decoder>(d: &mut D) -> Result<path::PathBuf, D::Error> {
+impl<D: Decoder> Decodable<D> for path::PathBuf {
+ fn decode(d: &mut D) -> Result<path::PathBuf, D::Error> {
let bytes: String = Decodable::decode(d)?;
Ok(path::PathBuf::from(bytes))
}
}
-impl<T: Encodable + Copy> Encodable for Cell<T> {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T: Encodable<S> + Copy> Encodable<S> for Cell<T> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
self.get().encode(s)
}
}
-impl<T: Decodable + Copy> Decodable for Cell<T> {
- fn decode<D: Decoder>(d: &mut D) -> Result<Cell<T>, D::Error> {
+impl<D: Decoder, T: Decodable<D> + Copy> Decodable<D> for Cell<T> {
+ fn decode(d: &mut D) -> Result<Cell<T>, D::Error> {
Ok(Cell::new(Decodable::decode(d)?))
}
}
// `encoder.error("attempting to Encode borrowed RefCell")`
// from `encode` when `try_borrow` returns `None`.
-impl<T: Encodable> Encodable for RefCell<T> {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T: Encodable<S>> Encodable<S> for RefCell<T> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
self.borrow().encode(s)
}
}
-impl<T: Decodable> Decodable for RefCell<T> {
- fn decode<D: Decoder>(d: &mut D) -> Result<RefCell<T>, D::Error> {
+impl<D: Decoder, T: Decodable<D>> Decodable<D> for RefCell<T> {
+ fn decode(d: &mut D) -> Result<RefCell<T>, D::Error> {
Ok(RefCell::new(Decodable::decode(d)?))
}
}
-impl<T: Encodable> Encodable for Arc<T> {
- fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T: Encodable<S>> Encodable<S> for Arc<T> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
(**self).encode(s)
}
}
-impl<T: Decodable> Decodable for Arc<T> {
- fn decode
<D: Decoder>(d: &mut D) -> Result<Arc<T>, D::Error> {
+impl<D: Decoder, T: Decodable<D>> Decodable<D> for Arc<T> {
+ fn decode(d: &mut D) -> Result<Arc<T>, D::Error> {
Ok(Arc::new(Decodable::decode(d)?))
}
}
-// ___________________________________________________________________________
-// Specialization-based interface for multi-dispatch Encodable/Decodable.
-
-/// Implement this trait on your `{Encodable,Decodable}::Error` types
-/// to override the default panic behavior for missing specializations.
-pub trait SpecializationError {
- /// Creates an error for a missing method specialization.
- /// Defaults to panicking with type, trait & method names.
- /// `S` is the encoder/decoder state type,
- /// `T` is the type being encoded/decoded, and
- /// the arguments are the names of the trait
- /// and method that should've been overridden.
- fn not_found<S, T: ?Sized>(trait_name: &'static str, method_name: &'static str) -> Self;
-}
-
-impl<E> SpecializationError for E {
- default fn not_found<S, T: ?Sized>(trait_name: &'static str, method_name: &'static str) -> E {
- panic!(
- "missing specialization: `<{} as {}<{}>>::{}` not overridden",
- any::type_name::<S>(),
- trait_name,
- any::type_name::<T>(),
- method_name
- );
- }
-}
-
-/// Implement this trait on encoders, with `T` being the type
-/// you want to encode (employing `UseSpecializedEncodable`),
-/// using a strategy specific to the encoder.
-pub trait SpecializedEncoder<T: ?Sized + UseSpecializedEncodable>: Encoder {
- /// Encode the value in a manner specific to this encoder state.
- fn specialized_encode(&mut self, value: &T) -> Result<(), Self::Error>;
-}
-
-impl<E: Encoder, T: ?Sized + UseSpecializedEncodable> SpecializedEncoder<T> for E {
- default fn specialized_encode(&mut self, value: &T) -> Result<(), E::Error> {
- value.default_encode(self)
- }
-}
-
-/// Implement this trait on decoders, with `T` being the type
-/// you want to decode (employing `UseSpecializedDecodable`),
-/// using a strategy specific to the decoder.
-pub trait SpecializedDecoder<T: UseSpecializedDecodable>: Decoder {
- /// Decode a value in a manner specific to this decoder state.
- fn specialized_decode(&mut self) -> Result<T, Self::Error>;
-}
-
-impl<D: Decoder, T: UseSpecializedDecodable> SpecializedDecoder<T> for D {
- default fn specialized_decode(&mut self) -> Result<T, D::Error> {
- T::default_decode(self)
- }
-}
-
-/// Implement this trait on your type to get an `Encodable`
-/// implementation which goes through `SpecializedEncoder`.
-pub trait UseSpecializedEncodable {
- /// Defaults to returning an error (see `SpecializationError`).
- fn default_encode<E: Encoder>(&self, _: &mut E) -> Result<(), E::Error> {
- Err(E::Error::not_found::<E, Self>("SpecializedEncoder", "specialized_encode"))
- }
-}
-
-impl<T: ?Sized + UseSpecializedEncodable> Encodable for T {
- default fn encode<E: Encoder>(&self, e: &mut E) -> Result<(), E::Error> {
- E::specialized_encode(e, self)
- }
-}
-
-/// Implement this trait on your type to get an `Decodable`
-/// implementation which goes through `SpecializedDecoder`.
-pub trait UseSpecializedDecodable: Sized {
- /// Defaults to returning an error (see `SpecializationError`).
- fn default_decode<D: Decoder>(_: &mut D) -> Result<Self, D::Error> {
- Err(D::Error::not_found::<D, Self>("SpecializedDecoder", "specialized_decode"))
- }
-}
-
-impl<T: UseSpecializedDecodable> Decodable for T {
- default fn decode<D: Decoder>(d: &mut D) -> Result<T, D::Error> {
- D::specialized_decode(d)
- }
-}
-
-// Can't avoid specialization for &T and Box<T> impls,
-// as proxy impls on them are blankets that conflict
-// with the Encodable and Decodable impls above,
-// which only have `default` on their methods
-// for this exact reason.
-// May be fixable in a simpler fashion via the
-// more complex lattice model for specialization.
-impl<'a, T: ?Sized + Encodable> UseSpecializedEncodable for &'a T {
- fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
- (**self).encode(s)
- }
-}
-impl<T: ?Sized + Encodable> UseSpecializedEncodable for Box<T> {
- fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+impl<S: Encoder, T: ?Sized + Encodable<S>> Encodable<S> for Box<T> {
+ fn encode(&self, s: &mut S) -> Result<(), S::Error> {
(**self).encode(s)
}
}
-impl<T: Decodable> UseSpecializedDecodable for Box<T> {
- fn default_decode<D: Decoder>(d: &mut D) -> Result<Box<T>, D::Error> {
+impl<D: Decoder, T: Decodable<D>> Decodable<D> for Box<T> {
+ fn decode(d: &mut D) -> Result<Box<T>, D::Error> {
Ok(box Decodable::decode(d)?)
}
}
-impl<'a, T: Decodable> UseSpecializedDecodable for &'a T {}
-impl<'a, T: Decodable> UseSpecializedDecodable for &'a [T] {}
projects / rust.git / blobdiff