diff options
Diffstat (limited to 'compiler/rustc_serialize/src/serialize.rs')
| -rw-r--r-- | compiler/rustc_serialize/src/serialize.rs | 183 |
1 files changed, 22 insertions, 161 deletions
diff --git a/compiler/rustc_serialize/src/serialize.rs b/compiler/rustc_serialize/src/serialize.rs index 36e575b2427..817a0c9dcb1 100644 --- a/compiler/rustc_serialize/src/serialize.rs +++ b/compiler/rustc_serialize/src/serialize.rs @@ -15,7 +15,6 @@ pub trait Encoder { type Error; // Primitive types: - fn emit_unit(&mut self) -> Result<(), Self::Error>; fn emit_usize(&mut self, v: usize) -> Result<(), Self::Error>; fn emit_u128(&mut self, v: u128) -> Result<(), Self::Error>; fn emit_u64(&mut self, v: u64) -> Result<(), Self::Error>; @@ -35,22 +34,8 @@ pub trait Encoder { fn emit_str(&mut self, v: &str) -> Result<(), Self::Error>; fn emit_raw_bytes(&mut self, s: &[u8]) -> Result<(), Self::Error>; - // Compound types: - #[inline] - fn emit_enum<F>(&mut self, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } - - fn emit_enum_variant<F>( - &mut self, - _v_name: &str, - v_id: usize, - _len: usize, - f: F, - ) -> Result<(), Self::Error> + // Convenience for the derive macro: + fn emit_enum_variant<F>(&mut self, v_id: usize, f: F) -> Result<(), Self::Error> where F: FnOnce(&mut Self) -> Result<(), Self::Error>, { @@ -65,112 +50,9 @@ pub trait Encoder { // optimization that would otherwise be necessary here, likely due to the // multiple levels of inlining and const-prop that are needed. #[inline] - fn emit_fieldless_enum_variant<const ID: usize>( - &mut self, - _v_name: &str, - ) -> Result<(), Self::Error> { + fn emit_fieldless_enum_variant<const ID: usize>(&mut self) -> Result<(), Self::Error> { self.emit_usize(ID) } - - #[inline] - fn emit_enum_variant_arg<F>(&mut self, _first: bool, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } - - #[inline] - fn emit_struct<F>(&mut self, _no_fields: bool, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } - - #[inline] - fn emit_struct_field<F>(&mut self, _f_name: &str, _first: bool, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } - - #[inline] - fn emit_tuple<F>(&mut self, _len: usize, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } - - #[inline] - fn emit_tuple_arg<F>(&mut self, _idx: usize, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } - - // Specialized types: - fn emit_option<F>(&mut self, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - self.emit_enum(f) - } - - #[inline] - fn emit_option_none(&mut self) -> Result<(), Self::Error> { - self.emit_enum_variant("None", 0, 0, |_| Ok(())) - } - - fn emit_option_some<F>(&mut self, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - self.emit_enum_variant("Some", 1, 1, f) - } - - fn emit_seq<F>(&mut self, len: usize, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - self.emit_usize(len)?; - f(self) - } - - #[inline] - fn emit_seq_elt<F>(&mut self, _idx: usize, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } - - fn emit_map<F>(&mut self, len: usize, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - self.emit_usize(len)?; - f(self) - } - - #[inline] - fn emit_map_elt_key<F>(&mut self, _idx: usize, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } - - #[inline] - fn emit_map_elt_val<F>(&mut self, f: F) -> Result<(), Self::Error> - where - F: FnOnce(&mut Self) -> Result<(), Self::Error>, - { - f(self) - } } // Note: all the methods in this trait are infallible, which may be surprising. @@ -320,8 +202,8 @@ impl<D: Decoder> Decodable<D> for String { } impl<S: Encoder> Encodable<S> for () { - fn encode(&self, s: &mut S) -> Result<(), S::Error> { - s.emit_unit() + fn encode(&self, _s: &mut S) -> Result<(), S::Error> { + Ok(()) } } @@ -330,8 +212,8 @@ impl<D: Decoder> Decodable<D> for () { } impl<S: Encoder, T> Encodable<S> for PhantomData<T> { - fn encode(&self, s: &mut S) -> Result<(), S::Error> { - s.emit_unit() + fn encode(&self, _s: &mut S) -> Result<(), S::Error> { + Ok(()) } } @@ -362,12 +244,11 @@ impl<D: Decoder, T: Decodable<D>> Decodable<D> for Rc<T> { impl<S: Encoder, T: Encodable<S>> Encodable<S> for [T] { default 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))? - } - Ok(()) - }) + s.emit_usize(self.len())?; + for e in self.iter() { + e.encode(s)? + } + Ok(()) } } @@ -450,10 +331,10 @@ impl<'a, D: Decoder> Decodable<D> for Cow<'a, str> { 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)), - }) + match *self { + None => s.emit_enum_variant(0, |_| Ok(())), + Some(ref v) => s.emit_enum_variant(1, |s| v.encode(s)), + } } } @@ -469,14 +350,10 @@ impl<D: Decoder, T: Decodable<D>> Decodable<D> for Option<T> { 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(|s| match *self { - Ok(ref v) => { - s.emit_enum_variant("Ok", 0, 1, |s| s.emit_enum_variant_arg(true, |s| v.encode(s))) - } - Err(ref v) => { - s.emit_enum_variant("Err", 1, 1, |s| s.emit_enum_variant_arg(true, |s| v.encode(s))) - } - }) + match *self { + Ok(ref v) => s.emit_enum_variant(0, |s| v.encode(s)), + Err(ref v) => s.emit_enum_variant(1, |s| v.encode(s)), + } } } @@ -494,18 +371,6 @@ macro_rules! peel { ($name:ident, $($other:ident,)*) => (tuple! { $($other,)* }) } -/// Evaluates to the number of tokens passed to it. -/// -/// Logarithmic counting: every one or two recursive expansions, the number of -/// tokens to count is divided by two, instead of being reduced by one. -/// Therefore, the recursion depth is the binary logarithm of the number of -/// tokens to count, and the expanded tree is likewise very small. -macro_rules! count { - ($one:tt) => (1usize); - ($($pairs:tt $_p:tt)*) => (count!($($pairs)*) << 1usize); - ($odd:tt $($rest:tt)*) => (count!($($rest)*) | 1usize); -} - macro_rules! tuple { () => (); ( $($name:ident,)+ ) => ( @@ -518,12 +383,8 @@ macro_rules! tuple { #[allow(non_snake_case)] fn encode(&self, s: &mut S) -> Result<(), S::Error> { let ($(ref $name,)+) = *self; - let len: usize = count!($($name)+); - s.emit_tuple(len, |s| { - let mut i = 0; - $(s.emit_tuple_arg({ i+=1; i-1 }, |s| $name.encode(s))?;)+ - Ok(()) - }) + $($name.encode(s)?;)+ + Ok(()) } } peel! { $($name,)+ } |