erased-serde-0.3.6/Cargo.toml.orig010066400017500001750000000011751333714503700152070ustar0000000000000000[package] name = "erased-serde" version = "0.3.6" authors = ["David Tolnay "] license = "MIT/Apache-2.0" description = "Type-erased Serialize and Serializer traits" repository = "https://github.com/dtolnay/erased-serde" documentation = "https://github.com/dtolnay/erased-serde" keywords = ["serde", "erasure"] include = ["Cargo.toml", "src/**/*.rs", "LICENSE-*"] [dependencies] serde = "1.0.63" [dev-dependencies] serde_cbor = "0.8" serde_derive = "1.0" serde_json = "1.0" [features] unstable-debug = [] [[test]] name = "test" path = "tests/readme.rs" [badges] travis-ci = { repository = "dtolnay/erased-serde" } erased-serde-0.3.6/Cargo.toml0000644000000023100000000000000114360ustar00# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO # # When uploading crates to the registry Cargo will automatically # "normalize" Cargo.toml files for maximal compatibility # with all versions of Cargo and also rewrite `path` dependencies # to registry (e.g. crates.io) dependencies # # If you believe there's an error in this file please file an # issue against the rust-lang/cargo repository. If you're # editing this file be aware that the upstream Cargo.toml # will likely look very different (and much more reasonable) [package] name = "erased-serde" version = "0.3.6" authors = ["David Tolnay "] include = ["Cargo.toml", "src/**/*.rs", "LICENSE-*"] description = "Type-erased Serialize and Serializer traits" documentation = "https://github.com/dtolnay/erased-serde" keywords = ["serde", "erasure"] license = "MIT/Apache-2.0" repository = "https://github.com/dtolnay/erased-serde" [[test]] name = "test" path = "tests/readme.rs" [dependencies.serde] version = "1.0.63" [dev-dependencies.serde_cbor] version = "0.8" [dev-dependencies.serde_derive] version = "1.0" [dev-dependencies.serde_json] version = "1.0" [features] unstable-debug = [] [badges.travis-ci] repository = "dtolnay/erased-serde" erased-serde-0.3.6/LICENSE-APACHE010066400017500001750000000251371275637762500142660ustar0000000000000000 Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. 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See the License for the specific language governing permissions and limitations under the License. erased-serde-0.3.6/LICENSE-MIT010066400017500001750000000020531275637764000137630ustar0000000000000000Copyright (c) 2016 Erased Serde Developers Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. erased-serde-0.3.6/src/any.rs010066400017500001750000000072441326675200600142500ustar0000000000000000use std::mem; #[cfg(feature = "unstable-debug")] use std::intrinsics; pub struct Any { ptr: *mut (), drop: fn(*mut ()), fingerprint: Fingerprint, /// For panic messages only. Not used for comparison. #[cfg(feature = "unstable-debug")] type_name: &'static str, } // These functions are all unsafe. They are not exposed to the user. Declaring // them as `unsafe fn` would not make the rest of erased-serde any safer or more // readable. impl Any { // This is unsafe -- caller must not hold on to the Any beyond the lifetime // of T. // // Example of bad code: // // let s = "bad".to_owned(); // let a = Any::new(&s); // drop(s); // // Now `a.view()` and `a.take()` return references to a dead String. pub(crate) fn new(t: T) -> Self { let ptr = Box::into_raw(Box::new(t)) as *mut (); let drop = |ptr| drop(unsafe { Box::from_raw(ptr as *mut T) }); let fingerprint = Fingerprint::of::(); // Once attributes on struct literal fields are stable, do that instead. // https://github.com/rust-lang/rust/issues/41681 #[cfg(not(feature = "unstable-debug"))] { Any { ptr, drop, fingerprint } } #[cfg(feature = "unstable-debug")] { let type_name = unsafe { intrinsics::type_name::() }; Any { ptr, drop, fingerprint, type_name } } } // This is unsafe -- caller is responsible that T is the correct type. pub(crate) fn view(&mut self) -> &mut T { if self.fingerprint != Fingerprint::of::() { self.invalid_cast_to::(); } let ptr = self.ptr as *mut T; unsafe { &mut *ptr } } // This is unsafe -- caller is responsible that T is the correct type. pub(crate) fn take(self) -> T { if self.fingerprint != Fingerprint::of::() { self.invalid_cast_to::(); } let ptr = self.ptr as *mut T; let box_t = unsafe { Box::from_raw(ptr) }; mem::forget(self); *box_t } #[cfg(not(feature = "unstable-debug"))] fn invalid_cast_to(&self) -> ! { panic!("invalid cast; enable `unstable-debug` feature to debug"); } #[cfg(feature = "unstable-debug")] fn invalid_cast_to(&self) -> ! { let from = self.type_name; let to = unsafe { intrinsics::type_name::() }; panic!("invalid cast: {} to {}", from, to); } } impl Drop for Any { fn drop(&mut self) { (self.drop)(self.ptr); } } #[derive(Debug, Eq, PartialEq)] struct Fingerprint { size: usize, align: usize, id: usize, } impl Fingerprint { fn of() -> Fingerprint { Fingerprint { size: mem::size_of::(), align: mem::align_of::(), // This is not foolproof -- theoretically Rust or LLVM could // deduplicate some or all of these methods. But in practice it's // great and I am comfortable relying on this in debug mode to catch // bugs early. id: Fingerprint::of:: as usize, } } } #[test] fn test_fingerprint() { assert_eq!(Fingerprint::of::(), Fingerprint::of::()); assert_eq!(Fingerprint::of::<&str>(), Fingerprint::of::<&'static str>()); assert_ne!(Fingerprint::of::(), Fingerprint::of::()); assert_ne!(Fingerprint::of::(), Fingerprint::of::<&usize>()); assert_ne!(Fingerprint::of::<&usize>(), Fingerprint::of::<&&usize>()); assert_ne!(Fingerprint::of::<&usize>(), Fingerprint::of::<&mut usize>()); struct A; struct B; assert_ne!(Fingerprint::of::(), Fingerprint::of::()); } erased-serde-0.3.6/src/de.rs010066400017500001750000001441661333714502300140500ustar0000000000000000use std::fmt::{self, Display}; use serde; use any::Any; use error::Error; /// Deserialize a value of type `T` from the given trait object. /// /// ```rust /// extern crate erased_serde; /// extern crate serde_json; /// extern crate serde_cbor; /// /// use std::collections::BTreeMap as Map; /// /// use erased_serde::Deserializer; /// /// fn main() { /// static JSON: &'static [u8] = br#"{"A": 65, "B": 66}"#; /// static CBOR: &'static [u8] = &[162, 97, 65, 24, 65, 97, 66, 24, 66]; /// /// // Construct some deserializers. /// let json = &mut serde_json::de::Deserializer::from_slice(JSON); /// let cbor = &mut serde_cbor::de::Deserializer::from_slice(CBOR); /// /// // The values in this map are boxed trait objects, which is not possible /// // with the normal serde::Deserializer because of object safety. /// let mut formats: Map<&str, Box> = Map::new(); /// formats.insert("json", Box::new(Deserializer::erase(json))); /// formats.insert("cbor", Box::new(Deserializer::erase(cbor))); /// /// // Pick a Deserializer out of the formats map. /// let format = formats.get_mut("json").unwrap(); /// /// let data: Map = erased_serde::deserialize(format).unwrap(); /// /// println!("{}", data["A"] + data["B"]); /// } /// ``` pub fn deserialize<'de, T>(deserializer: &mut Deserializer<'de>) -> Result where T: serde::Deserialize<'de> { serde::Deserialize::deserialize(deserializer) } // TRAITS ////////////////////////////////////////////////////////////////////// pub trait DeserializeSeed<'de> { fn erased_deserialize_seed(&mut self, &mut Deserializer<'de>) -> Result; } /// An object-safe equivalent of Serde's `Deserializer` trait. /// /// Any implementation of Serde's `Deserializer` can be converted to an /// `&erased_serde::Deserializer` or `Box` trait /// object using `erased_serde::Deserializer::erase`. /// /// ```rust /// extern crate erased_serde; /// extern crate serde_json; /// extern crate serde_cbor; /// /// use std::collections::BTreeMap as Map; /// /// use erased_serde::Deserializer; /// /// fn main() { /// static JSON: &'static [u8] = br#"{"A": 65, "B": 66}"#; /// static CBOR: &'static [u8] = &[162, 97, 65, 24, 65, 97, 66, 24, 66]; /// /// // Construct some deserializers. /// let json = &mut serde_json::de::Deserializer::from_slice(JSON); /// let cbor = &mut serde_cbor::de::Deserializer::from_slice(CBOR); /// /// // The values in this map are boxed trait objects, which is not possible /// // with the normal serde::Deserializer because of object safety. /// let mut formats: Map<&str, Box> = Map::new(); /// formats.insert("json", Box::new(Deserializer::erase(json))); /// formats.insert("cbor", Box::new(Deserializer::erase(cbor))); /// /// // Pick a Deserializer out of the formats map. /// let format = formats.get_mut("json").unwrap(); /// /// let data: Map = erased_serde::deserialize(format).unwrap(); /// /// println!("{}", data["A"] + data["B"]); /// } /// ``` pub trait Deserializer<'de> { fn erased_deserialize_any(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_bool(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_u8(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_u16(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_u32(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_u64(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_i8(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_i16(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_i32(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_i64(&mut self, &mut Visitor<'de>) -> Result; serde_if_integer128! { fn erased_deserialize_i128(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_u128(&mut self, &mut Visitor<'de>) -> Result; } fn erased_deserialize_f32(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_f64(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_char(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_str(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_string(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_bytes(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_byte_buf(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_option(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_unit(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_unit_struct(&mut self, name: &'static str, &mut Visitor<'de>) -> Result; fn erased_deserialize_newtype_struct(&mut self, name: &'static str, &mut Visitor<'de>) -> Result; fn erased_deserialize_seq(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_tuple(&mut self, len: usize, &mut Visitor<'de>) -> Result; fn erased_deserialize_tuple_struct(&mut self, name: &'static str, len: usize, &mut Visitor<'de>) -> Result; fn erased_deserialize_map(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_struct(&mut self, name: &'static str, fields: &'static [&'static str], &mut Visitor<'de>) -> Result; fn erased_deserialize_identifier(&mut self, &mut Visitor<'de>) -> Result; fn erased_deserialize_enum(&mut self, name: &'static str, variants: &'static [&'static str], &mut Visitor<'de>) -> Result; fn erased_deserialize_ignored_any(&mut self, &mut Visitor<'de>) -> Result; fn erased_is_human_readable(&self) -> bool; } pub trait Visitor<'de> { fn erased_expecting(&self, &mut fmt::Formatter) -> fmt::Result; fn erased_visit_bool(&mut self, bool) -> Result; fn erased_visit_i8(&mut self, i8) -> Result; fn erased_visit_i16(&mut self, i16) -> Result; fn erased_visit_i32(&mut self, i32) -> Result; fn erased_visit_i64(&mut self, i64) -> Result; fn erased_visit_u8(&mut self, u8) -> Result; fn erased_visit_u16(&mut self, u16) -> Result; fn erased_visit_u32(&mut self, u32) -> Result; fn erased_visit_u64(&mut self, u64) -> Result; serde_if_integer128! { fn erased_visit_i128(&mut self, i128) -> Result; fn erased_visit_u128(&mut self, u128) -> Result; } fn erased_visit_f32(&mut self, f32) -> Result; fn erased_visit_f64(&mut self, f64) -> Result; fn erased_visit_char(&mut self, char) -> Result; fn erased_visit_str(&mut self, &str) -> Result; fn erased_visit_borrowed_str(&mut self, &'de str) -> Result; fn erased_visit_string(&mut self, String) -> Result; fn erased_visit_bytes(&mut self, &[u8]) -> Result; fn erased_visit_borrowed_bytes(&mut self, &'de [u8]) -> Result; fn erased_visit_byte_buf(&mut self, Vec) -> Result; fn erased_visit_none(&mut self) -> Result; fn erased_visit_some(&mut self, &mut Deserializer<'de>) -> Result; fn erased_visit_unit(&mut self) -> Result; fn erased_visit_newtype_struct(&mut self, &mut Deserializer<'de>) -> Result; fn erased_visit_seq(&mut self, &mut SeqAccess<'de>) -> Result; fn erased_visit_map(&mut self, &mut MapAccess<'de>) -> Result; fn erased_visit_enum(&mut self, &mut EnumAccess<'de>) -> Result; } pub trait SeqAccess<'de> { fn erased_next_element(&mut self, &mut DeserializeSeed<'de>) -> Result, Error>; fn erased_size_hint(&self) -> Option; } pub trait MapAccess<'de> { fn erased_next_key(&mut self, &mut DeserializeSeed<'de>) -> Result, Error>; fn erased_next_value(&mut self, &mut DeserializeSeed<'de>) -> Result; fn erased_next_entry(&mut self, key: &mut DeserializeSeed<'de>, value: &mut DeserializeSeed<'de>) -> Result, Error>; fn erased_size_hint(&self) -> Option; } pub trait EnumAccess<'de> { fn erased_variant_seed(&mut self, &mut DeserializeSeed<'de>) -> Result<(Out, Variant<'de>), Error>; } impl<'de> Deserializer<'de> { /// Convert any Serde `Deserializer` to a trait object. /// /// ```rust /// extern crate erased_serde; /// extern crate serde_json; /// extern crate serde_cbor; /// /// use std::collections::BTreeMap as Map; /// /// use erased_serde::Deserializer; /// /// fn main() { /// static JSON: &'static [u8] = br#"{"A": 65, "B": 66}"#; /// static CBOR: &'static [u8] = &[162, 97, 65, 24, 65, 97, 66, 24, 66]; /// /// // Construct some deserializers. /// let json = &mut serde_json::de::Deserializer::from_slice(JSON); /// let cbor = &mut serde_cbor::de::Deserializer::from_slice(CBOR); /// /// // The values in this map are boxed trait objects, which is not possible /// // with the normal serde::Deserializer because of object safety. /// let mut formats: Map<&str, Box> = Map::new(); /// formats.insert("json", Box::new(Deserializer::erase(json))); /// formats.insert("cbor", Box::new(Deserializer::erase(cbor))); /// /// // Pick a Deserializer out of the formats map. /// let format = formats.get_mut("json").unwrap(); /// /// let data: Map = erased_serde::deserialize(format).unwrap(); /// /// println!("{}", data["A"] + data["B"]); /// } /// ``` pub fn erase(deserializer: D) -> erase::Deserializer where D: serde::Deserializer<'de> { erase::Deserializer { state: Some(deserializer) } } } // OUT ///////////////////////////////////////////////////////////////////////// pub struct Out(Any); impl Out { fn new(t: T) -> Self { Out(Any::new(t)) } fn take(self) -> T { self.0.take() } } // IMPL ERASED SERDE FOR SERDE ///////////////////////////////////////////////// mod erase { pub struct DeserializeSeed { pub(crate) state: Option, } impl DeserializeSeed { pub(crate) fn take(&mut self) -> D { self.state.take().unwrap() } } pub struct Deserializer { pub(crate) state: Option, } impl Deserializer { pub(crate) fn take(&mut self) -> D { self.state.take().unwrap() } pub(crate) fn as_ref(&self) -> &D { self.state.as_ref().unwrap() } } pub struct Visitor { pub(crate) state: Option, } impl Visitor { pub(crate) fn take(&mut self) -> D { self.state.take().unwrap() } pub(crate) fn as_ref(&self) -> &D { self.state.as_ref().unwrap() } } pub struct SeqAccess { pub(crate) state: D, } impl SeqAccess { pub(crate) fn as_ref(&self) -> &D { &self.state } pub(crate) fn as_mut(&mut self) -> &mut D { &mut self.state } } pub struct MapAccess { pub(crate) state: D, } impl MapAccess { pub(crate) fn as_ref(&self) -> &D { &self.state } pub(crate) fn as_mut(&mut self) -> &mut D { &mut self.state } } pub struct EnumAccess { pub(crate) state: Option, } impl EnumAccess { pub(crate) fn take(&mut self) -> D { self.state.take().unwrap() } } } impl<'de, T> DeserializeSeed<'de> for erase::DeserializeSeed where T: serde::de::DeserializeSeed<'de> { fn erased_deserialize_seed(&mut self, deserializer: &mut Deserializer<'de>) -> Result { self.take().deserialize(deserializer).map(Out::new) } } impl<'de, T> Deserializer<'de> for erase::Deserializer where T: serde::Deserializer<'de> { fn erased_deserialize_any(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_any(visitor).map_err(erase) } fn erased_deserialize_bool(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_bool(visitor).map_err(erase) } fn erased_deserialize_u8(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_u8(visitor).map_err(erase) } fn erased_deserialize_u16(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_u16(visitor).map_err(erase) } fn erased_deserialize_u32(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_u32(visitor).map_err(erase) } fn erased_deserialize_u64(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_u64(visitor).map_err(erase) } fn erased_deserialize_i8(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_i8(visitor).map_err(erase) } fn erased_deserialize_i16(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_u16(visitor).map_err(erase) } fn erased_deserialize_i32(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_i32(visitor).map_err(erase) } fn erased_deserialize_i64(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_i64(visitor).map_err(erase) } serde_if_integer128! { fn erased_deserialize_i128(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_i128(visitor).map_err(erase) } fn erased_deserialize_u128(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_u128(visitor).map_err(erase) } } fn erased_deserialize_f32(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_f32(visitor).map_err(erase) } fn erased_deserialize_f64(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_f64(visitor).map_err(erase) } fn erased_deserialize_char(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_char(visitor).map_err(erase) } fn erased_deserialize_str(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_str(visitor).map_err(erase) } fn erased_deserialize_string(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_string(visitor).map_err(erase) } fn erased_deserialize_bytes(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_bytes(visitor).map_err(erase) } fn erased_deserialize_byte_buf(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_byte_buf(visitor).map_err(erase) } fn erased_deserialize_option(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_option(visitor).map_err(erase) } fn erased_deserialize_unit(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_unit(visitor).map_err(erase) } fn erased_deserialize_unit_struct(&mut self, name: &'static str, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_unit_struct(name, visitor).map_err(erase) } fn erased_deserialize_newtype_struct(&mut self, name: &'static str, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_newtype_struct(name, visitor).map_err(erase) } fn erased_deserialize_seq(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_seq(visitor).map_err(erase) } fn erased_deserialize_tuple(&mut self, len: usize, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_tuple(len, visitor).map_err(erase) } fn erased_deserialize_tuple_struct(&mut self, name: &'static str, len: usize, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_tuple_struct(name, len, visitor).map_err(erase) } fn erased_deserialize_map(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_map(visitor).map_err(erase) } fn erased_deserialize_struct(&mut self, name: &'static str, fields: &'static [&'static str], visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_struct(name, fields, visitor).map_err(erase) } fn erased_deserialize_identifier(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_identifier(visitor).map_err(erase) } fn erased_deserialize_enum(&mut self, name: &'static str, variants: &'static [&'static str], visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_enum(name, variants, visitor).map_err(erase) } fn erased_deserialize_ignored_any(&mut self, visitor: &mut Visitor<'de>) -> Result { self.take().deserialize_ignored_any(visitor).map_err(erase) } fn erased_is_human_readable(&self) -> bool { self.as_ref().is_human_readable() } } impl<'de, T> Visitor<'de> for erase::Visitor where T: serde::de::Visitor<'de> { fn erased_expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { self.as_ref().expecting(formatter) } fn erased_visit_bool(&mut self, v: bool) -> Result { self.take().visit_bool(v).map(Out::new) } fn erased_visit_i8(&mut self, v: i8) -> Result { self.take().visit_i8(v).map(Out::new) } fn erased_visit_i16(&mut self, v: i16) -> Result { self.take().visit_i16(v).map(Out::new) } fn erased_visit_i32(&mut self, v: i32) -> Result { self.take().visit_i32(v).map(Out::new) } fn erased_visit_i64(&mut self, v: i64) -> Result { self.take().visit_i64(v).map(Out::new) } fn erased_visit_u8(&mut self, v: u8) -> Result { self.take().visit_u8(v).map(Out::new) } fn erased_visit_u16(&mut self, v: u16) -> Result { self.take().visit_u16(v).map(Out::new) } fn erased_visit_u32(&mut self, v: u32) -> Result { self.take().visit_u32(v).map(Out::new) } fn erased_visit_u64(&mut self, v: u64) -> Result { self.take().visit_u64(v).map(Out::new) } serde_if_integer128! { fn erased_visit_i128(&mut self, v: i128) -> Result { self.take().visit_i128(v).map(Out::new) } fn erased_visit_u128(&mut self, v: u128) -> Result { self.take().visit_u128(v).map(Out::new) } } fn erased_visit_f32(&mut self, v: f32) -> Result { self.take().visit_f32(v).map(Out::new) } fn erased_visit_f64(&mut self, v: f64) -> Result { self.take().visit_f64(v).map(Out::new) } fn erased_visit_char(&mut self, v: char) -> Result { self.take().visit_char(v).map(Out::new) } fn erased_visit_str(&mut self, v: &str) -> Result { self.take().visit_str(v).map(Out::new) } fn erased_visit_borrowed_str(&mut self, v: &'de str) -> Result { self.take().visit_borrowed_str(v).map(Out::new) } fn erased_visit_string(&mut self, v: String) -> Result { self.take().visit_string(v).map(Out::new) } fn erased_visit_bytes(&mut self, v: &[u8]) -> Result { self.take().visit_bytes(v).map(Out::new) } fn erased_visit_borrowed_bytes(&mut self, v: &'de [u8]) -> Result { self.take().visit_borrowed_bytes(v).map(Out::new) } fn erased_visit_byte_buf(&mut self, v: Vec) -> Result { self.take().visit_byte_buf(v).map(Out::new) } fn erased_visit_none(&mut self) -> Result { self.take().visit_none().map(Out::new) } fn erased_visit_some(&mut self, deserializer: &mut Deserializer<'de>) -> Result { self.take().visit_some(deserializer).map(Out::new) } fn erased_visit_unit(&mut self) -> Result { self.take().visit_unit().map(Out::new) } fn erased_visit_newtype_struct(&mut self, deserializer: &mut Deserializer<'de>) -> Result { self.take().visit_newtype_struct(deserializer).map(Out::new) } fn erased_visit_seq(&mut self, seq: &mut SeqAccess<'de>) -> Result { self.take().visit_seq(seq).map(Out::new) } fn erased_visit_map(&mut self, map: &mut MapAccess<'de>) -> Result { self.take().visit_map(map).map(Out::new) } fn erased_visit_enum(&mut self, data: &mut EnumAccess<'de>) -> Result { self.take().visit_enum(data).map(Out::new) } } impl<'de, T> SeqAccess<'de> for erase::SeqAccess where T: serde::de::SeqAccess<'de> { fn erased_next_element(&mut self, seed: &mut DeserializeSeed<'de>) -> Result, Error> { self.as_mut().next_element_seed(seed).map_err(erase) } fn erased_size_hint(&self) -> Option { self.as_ref().size_hint() } } impl<'de, T> MapAccess<'de> for erase::MapAccess where T: serde::de::MapAccess<'de> { fn erased_next_key(&mut self, seed: &mut DeserializeSeed<'de>) -> Result, Error> { self.as_mut().next_key_seed(seed).map_err(erase) } fn erased_next_value(&mut self, seed: &mut DeserializeSeed<'de>) -> Result { self.as_mut().next_value_seed(seed).map_err(erase) } fn erased_next_entry(&mut self, k: &mut DeserializeSeed<'de>, v: &mut DeserializeSeed<'de>) -> Result, Error> { self.as_mut().next_entry_seed(k, v).map_err(erase) } fn erased_size_hint(&self) -> Option { self.as_ref().size_hint() } } impl<'de, T> EnumAccess<'de> for erase::EnumAccess where T: serde::de::EnumAccess<'de> { fn erased_variant_seed(&mut self, seed: &mut DeserializeSeed<'de>) -> Result<(Out, Variant<'de>), Error> { self.take().variant_seed(seed).map(|(out, variant)| { use serde::de::VariantAccess; let erased = Variant { data: Any::new(variant), unit_variant: |a| { a.take::().unit_variant().map_err(erase) }, visit_newtype: |a, seed| { a.take::().newtype_variant_seed(seed).map_err(erase) }, tuple_variant: |a, len, visitor| { a.take::().tuple_variant(len, visitor).map_err(erase) }, struct_variant: |a, fields, visitor| { a.take::().struct_variant(fields, visitor).map_err(erase) }, }; (out, erased) }).map_err(erase) } } // IMPL SERDE FOR ERASED SERDE ///////////////////////////////////////////////// impl<'de, 'a> serde::de::DeserializeSeed<'de> for &'a mut DeserializeSeed<'de> { type Value = Out; fn deserialize(self, deserializer: D) -> Result where D: serde::Deserializer<'de> { let mut erased = erase::Deserializer { state: Some(deserializer) }; self.erased_deserialize_seed(&mut erased).map_err(unerase) } } macro_rules! impl_deserializer_for_trait_object { ({$($generics:tt)*} {$($mut:tt)*} $ty:ty) => { impl <$($generics)*> serde::Deserializer<'de> for $ty { type Error = Error; fn deserialize_any($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_any(&mut erased).map(Out::take) } fn deserialize_bool($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_bool(&mut erased).map(Out::take) } fn deserialize_u8($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_u8(&mut erased).map(Out::take) } fn deserialize_u16($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_u16(&mut erased).map(Out::take) } fn deserialize_u32($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_u32(&mut erased).map(Out::take) } fn deserialize_u64($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_u64(&mut erased).map(Out::take) } fn deserialize_i8($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_i8(&mut erased).map(Out::take) } fn deserialize_i16($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_i16(&mut erased).map(Out::take) } fn deserialize_i32($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_i32(&mut erased).map(Out::take) } fn deserialize_i64($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_i64(&mut erased).map(Out::take) } serde_if_integer128! { fn deserialize_i128($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_i128(&mut erased).map(Out::take) } fn deserialize_u128($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_u128(&mut erased).map(Out::take) } } fn deserialize_f32($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_f32(&mut erased).map(Out::take) } fn deserialize_f64($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_f64(&mut erased).map(Out::take) } fn deserialize_char($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_char(&mut erased).map(Out::take) } fn deserialize_str($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_str(&mut erased).map(Out::take) } fn deserialize_string($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_string(&mut erased).map(Out::take) } fn deserialize_bytes($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_bytes(&mut erased).map(Out::take) } fn deserialize_byte_buf($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_byte_buf(&mut erased).map(Out::take) } fn deserialize_option($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_option(&mut erased).map(Out::take) } fn deserialize_unit($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_unit(&mut erased).map(Out::take) } fn deserialize_unit_struct($($mut)* self, name: &'static str, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_unit_struct(name, &mut erased).map(Out::take) } fn deserialize_newtype_struct($($mut)* self, name: &'static str, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_newtype_struct(name, &mut erased).map(Out::take) } fn deserialize_seq($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_seq(&mut erased).map(Out::take) } fn deserialize_tuple($($mut)* self, len: usize, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_tuple(len, &mut erased).map(Out::take) } fn deserialize_tuple_struct($($mut)* self, name: &'static str, len: usize, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_tuple_struct(name, len, &mut erased).map(Out::take) } fn deserialize_map($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_map(&mut erased).map(Out::take) } fn deserialize_struct($($mut)* self, name: &'static str, fields: &'static [&'static str], visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_struct(name, fields, &mut erased).map(Out::take) } fn deserialize_identifier($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_identifier(&mut erased).map(Out::take) } fn deserialize_enum($($mut)* self, name: &'static str, variants: &'static [&'static str], visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_enum(name, variants, &mut erased).map(Out::take) } fn deserialize_ignored_any($($mut)* self, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; self.erased_deserialize_ignored_any(&mut erased).map(Out::take) } fn is_human_readable(&self) -> bool { self.erased_is_human_readable() } } }; } impl_deserializer_for_trait_object!({'de, 'a} {} &'a mut Deserializer<'de>); impl_deserializer_for_trait_object!({'de, 'a} {} &'a mut (Deserializer<'de> + Send)); impl_deserializer_for_trait_object!({'de, 'a} {} &'a mut (Deserializer<'de> + Sync)); impl_deserializer_for_trait_object!({'de, 'a} {} &'a mut (Deserializer<'de> + Send + Sync)); impl_deserializer_for_trait_object!({'de} {mut} Box>); impl_deserializer_for_trait_object!({'de} {mut} Box + Send>); impl_deserializer_for_trait_object!({'de} {mut} Box + Sync>); impl_deserializer_for_trait_object!({'de} {mut} Box + Send + Sync>); impl<'de, 'a> serde::de::Visitor<'de> for &'a mut Visitor<'de> { type Value = Out; fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { (**self).erased_expecting(formatter) } fn visit_bool(self, v: bool) -> Result where E: serde::de::Error { self.erased_visit_bool(v).map_err(unerase) } fn visit_i8(self, v: i8) -> Result where E: serde::de::Error { self.erased_visit_i8(v).map_err(unerase) } fn visit_i16(self, v: i16) -> Result where E: serde::de::Error { self.erased_visit_i16(v).map_err(unerase) } fn visit_i32(self, v: i32) -> Result where E: serde::de::Error { self.erased_visit_i32(v).map_err(unerase) } fn visit_i64(self, v: i64) -> Result where E: serde::de::Error { self.erased_visit_i64(v).map_err(unerase) } fn visit_u8(self, v: u8) -> Result where E: serde::de::Error { self.erased_visit_u8(v).map_err(unerase) } fn visit_u16(self, v: u16) -> Result where E: serde::de::Error { self.erased_visit_u16(v).map_err(unerase) } fn visit_u32(self, v: u32) -> Result where E: serde::de::Error { self.erased_visit_u32(v).map_err(unerase) } fn visit_u64(self, v: u64) -> Result where E: serde::de::Error { self.erased_visit_u64(v).map_err(unerase) } serde_if_integer128! { fn visit_i128(self, v: i128) -> Result where E: serde::de::Error { self.erased_visit_i128(v).map_err(unerase) } fn visit_u128(self, v: u128) -> Result where E: serde::de::Error { self.erased_visit_u128(v).map_err(unerase) } } fn visit_f32(self, v: f32) -> Result where E: serde::de::Error { self.erased_visit_f32(v).map_err(unerase) } fn visit_f64(self, v: f64) -> Result where E: serde::de::Error { self.erased_visit_f64(v).map_err(unerase) } fn visit_char(self, v: char) -> Result where E: serde::de::Error { self.erased_visit_char(v).map_err(unerase) } fn visit_str(self, v: &str) -> Result where E: serde::de::Error { self.erased_visit_str(v).map_err(unerase) } fn visit_borrowed_str(self, v: &'de str) -> Result where E: serde::de::Error { self.erased_visit_borrowed_str(v).map_err(unerase) } fn visit_string(self, v: String) -> Result where E: serde::de::Error { self.erased_visit_string(v).map_err(unerase) } fn visit_bytes(self, v: &[u8]) -> Result where E: serde::de::Error { self.erased_visit_bytes(v).map_err(unerase) } fn visit_borrowed_bytes(self, v: &'de [u8]) -> Result where E: serde::de::Error { self.erased_visit_borrowed_bytes(v).map_err(unerase) } fn visit_byte_buf(self, v: Vec) -> Result where E: serde::de::Error { self.erased_visit_byte_buf(v).map_err(unerase) } fn visit_none(self) -> Result where E: serde::de::Error { self.erased_visit_none().map_err(unerase) } fn visit_some(self, deserializer: D) -> Result where D: serde::Deserializer<'de> { let mut erased = erase::Deserializer { state: Some(deserializer) }; self.erased_visit_some(&mut erased).map_err(unerase) } fn visit_unit(self) -> Result where E: serde::de::Error { self.erased_visit_unit().map_err(unerase) } fn visit_newtype_struct(self, deserializer: D) -> Result where D: serde::Deserializer<'de> { let mut erased = erase::Deserializer { state: Some(deserializer) }; self.erased_visit_newtype_struct(&mut erased).map_err(unerase) } fn visit_seq(self, seq: V) -> Result where V: serde::de::SeqAccess<'de> { let mut erased = erase::SeqAccess { state: seq }; self.erased_visit_seq(&mut erased).map_err(unerase) } fn visit_map(self, map: V) -> Result where V: serde::de::MapAccess<'de> { let mut erased = erase::MapAccess { state: map }; self.erased_visit_map(&mut erased).map_err(unerase) } fn visit_enum(self, data: V) -> Result where V: serde::de::EnumAccess<'de> { let mut erased = erase::EnumAccess { state: Some(data) }; self.erased_visit_enum(&mut erased).map_err(unerase) } } impl<'de, 'a> serde::de::SeqAccess<'de> for &'a mut SeqAccess<'de> { type Error = Error; fn next_element_seed(&mut self, seed: T) -> Result, Error> where T: serde::de::DeserializeSeed<'de> { let mut seed = erase::DeserializeSeed { state: Some(seed) }; (**self).erased_next_element(&mut seed).map(|opt| opt.map(Out::take)) } fn size_hint(&self) -> Option { (**self).erased_size_hint() } } impl<'de, 'a> serde::de::MapAccess<'de> for &'a mut MapAccess<'de> { type Error = Error; fn next_key_seed(&mut self, seed: K) -> Result, Error> where K: serde::de::DeserializeSeed<'de> { let mut erased = erase::DeserializeSeed { state: Some(seed) }; (**self).erased_next_key(&mut erased).map(|opt| opt.map(Out::take)) } fn next_value_seed(&mut self, seed: V) -> Result where V: serde::de::DeserializeSeed<'de> { let mut erased = erase::DeserializeSeed { state: Some(seed) }; (**self).erased_next_value(&mut erased).map(Out::take) } fn size_hint(&self) -> Option { (**self).erased_size_hint() } } impl<'de, 'a> serde::de::EnumAccess<'de> for &'a mut EnumAccess<'de> { type Error = Error; type Variant = Variant<'de>; fn variant_seed(self, seed: V) -> Result<(V::Value, Self::Variant), Self::Error> where V: serde::de::DeserializeSeed<'de> { let mut erased = erase::DeserializeSeed { state: Some(seed) }; self.erased_variant_seed(&mut erased).map(|(out, variant)| (out.take(), variant)) } } pub struct Variant<'de> { data: Any, unit_variant: fn(Any) -> Result<(), Error>, visit_newtype: fn(Any, seed: &mut DeserializeSeed<'de>) -> Result, tuple_variant: fn(Any, len: usize, visitor: &mut Visitor<'de>) -> Result, struct_variant: fn(Any, fields: &'static [&'static str], visitor: &mut Visitor<'de>) -> Result, } impl<'de> serde::de::VariantAccess<'de> for Variant<'de> { type Error = Error; fn unit_variant(self) -> Result<(), Error> { (self.unit_variant)(self.data) } fn newtype_variant_seed(self, seed: T) -> Result where T: serde::de::DeserializeSeed<'de> { let mut erased = erase::DeserializeSeed { state: Some(seed) }; (self.visit_newtype)(self.data, &mut erased).map(Out::take) } fn tuple_variant(self, len: usize, visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; (self.tuple_variant)(self.data, len, &mut erased).map(Out::take) } fn struct_variant(self, fields: &'static [&'static str], visitor: V) -> Result where V: serde::de::Visitor<'de> { let mut erased = erase::Visitor { state: Some(visitor) }; (self.struct_variant)(self.data, fields, &mut erased).map(Out::take) } } // IMPL ERASED SERDE FOR ERASED SERDE ////////////////////////////////////////// macro_rules! deref_erased_deserializer { ($($imp:tt)+) => { impl $($imp)+ { fn erased_deserialize_any(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_any(visitor) } fn erased_deserialize_bool(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_bool(visitor) } fn erased_deserialize_u8(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_u8(visitor) } fn erased_deserialize_u16(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_u16(visitor) } fn erased_deserialize_u32(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_u32(visitor) } fn erased_deserialize_u64(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_u64(visitor) } fn erased_deserialize_i8(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_i8(visitor) } fn erased_deserialize_i16(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_i16(visitor) } fn erased_deserialize_i32(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_i32(visitor) } fn erased_deserialize_i64(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_i64(visitor) } serde_if_integer128! { fn erased_deserialize_i128(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_i128(visitor) } fn erased_deserialize_u128(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_u128(visitor) } } fn erased_deserialize_f32(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_f32(visitor) } fn erased_deserialize_f64(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_f64(visitor) } fn erased_deserialize_char(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_char(visitor) } fn erased_deserialize_str(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_str(visitor) } fn erased_deserialize_string(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_string(visitor) } fn erased_deserialize_bytes(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_bytes(visitor) } fn erased_deserialize_byte_buf(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_byte_buf(visitor) } fn erased_deserialize_option(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_option(visitor) } fn erased_deserialize_unit(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_unit(visitor) } fn erased_deserialize_unit_struct(&mut self, name: &'static str, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_unit_struct(name, visitor) } fn erased_deserialize_newtype_struct(&mut self, name: &'static str, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_newtype_struct(name, visitor) } fn erased_deserialize_seq(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_seq(visitor) } fn erased_deserialize_tuple(&mut self, len: usize, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_tuple(len, visitor) } fn erased_deserialize_tuple_struct(&mut self, name: &'static str, len: usize, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_tuple_struct(name, len, visitor) } fn erased_deserialize_map(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_map(visitor) } fn erased_deserialize_struct(&mut self, name: &'static str, fields: &'static [&'static str], visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_struct(name, fields, visitor) } fn erased_deserialize_identifier(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_identifier(visitor) } fn erased_deserialize_enum(&mut self, name: &'static str, variants: &'static [&'static str], visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_enum(name, variants, visitor) } fn erased_deserialize_ignored_any(&mut self, visitor: &mut Visitor<'de>) -> Result { (**self).erased_deserialize_ignored_any(visitor) } fn erased_is_human_readable(&self) -> bool { (**self).erased_is_human_readable() } } }; } deref_erased_deserializer!(<'de, 'a> Deserializer<'de> for Box + 'a>); deref_erased_deserializer!(<'de, 'a> Deserializer<'de> for Box + Send + 'a>); deref_erased_deserializer!(<'de, 'a> Deserializer<'de> for Box + Sync + 'a>); deref_erased_deserializer!(<'de, 'a> Deserializer<'de> for Box + Send + Sync + 'a>); deref_erased_deserializer!(<'de, 'a, T: ?Sized + Deserializer<'de>> Deserializer<'de> for &'a mut T); // ERROR /////////////////////////////////////////////////////////////////////// fn erase(e: E) -> Error where E: Display { serde::de::Error::custom(e) } fn unerase(e: Error) -> E where E: serde::de::Error { use std::error::Error; E::custom(e.description()) } // TEST //////////////////////////////////////////////////////////////////////// #[cfg(test)] mod tests { use super::*; use serde_json; use std::fmt::Debug; fn test_json<'de, T>(json: &'de [u8]) where T: serde::Deserialize<'de> + PartialEq + Debug { let expected: T = serde_json::from_slice(json).unwrap(); // test borrowed trait object { let mut de = serde_json::Deserializer::from_slice(json); let de: &mut Deserializer = &mut Deserializer::erase(&mut de); assert_eq!(expected, deserialize::(de).unwrap()); } // test boxed trait object { let mut de = serde_json::Deserializer::from_slice(json); let mut de: Box = Box::new(Deserializer::erase(&mut de)); assert_eq!(expected, deserialize::(&mut de).unwrap()); } } #[test] fn test_value() { test_json::(br#"["a", 1, [true], {"a": 1}]"#); } #[test] fn test_struct() { #[derive(Deserialize, PartialEq, Debug)] struct S { f: usize, } test_json::(br#"{"f":256}"#); } #[test] fn test_enum() { #[derive(Deserialize, PartialEq, Debug)] enum E { Unit, Newtype(bool), Tuple(bool, bool), Struct { t: bool, f: bool }, } test_json::(br#""Unit""#); test_json::(br#"{"Newtype":true}"#); test_json::(br#"{"Tuple":[true,false]}"#); test_json::(br#"{"Struct":{"t":true,"f":false}}"#); } #[test] fn test_borrowed() { let bytes = br#""borrowed""#.to_owned(); test_json::<&str>(&bytes); } #[test] fn assert_deserializer() { fn assert<'de, T: serde::Deserializer<'de>>() {} assert::<&mut Deserializer>(); assert::<&mut (Deserializer + Send)>(); assert::<&mut (Deserializer + Sync)>(); assert::<&mut (Deserializer + Send + Sync)>(); assert::<&mut (Deserializer + Sync + Send)>(); assert::>(); assert::>(); assert::>(); assert::>(); assert::>(); } } erased-serde-0.3.6/src/error.rs010066400017500001750000000013131326675200600146010ustar0000000000000000use std::error; use std::fmt::{self, Display}; use serde; /// Error when a `Serializer` or `Deserializer` trait object fails. #[derive(Debug)] pub struct Error { msg: String, } impl Display for Error { fn fmt(&self, formatter: &mut fmt::Formatter) -> Result<(), fmt::Error> { self.msg.fmt(formatter) } } impl error::Error for Error { fn description(&self) -> &str { &self.msg } } impl serde::ser::Error for Error { fn custom(msg: T) -> Self { Error { msg: msg.to_string(), } } } impl serde::de::Error for Error { fn custom(msg: T) -> Self { Error { msg: msg.to_string(), } } } erased-serde-0.3.6/src/lib.rs010066400017500001750000000075661333714504100142300ustar0000000000000000//! This crate provides type-erased versions of Serde's `Serialize`, `Serializer` //! and `Deserializer` traits that can be used as [trait //! objects](https://doc.rust-lang.org/book/trait-objects.html). //! //! The usual Serde `Serialize`, `Serializer` and `Deserializer` traits cannot //! be used as trait objects like `&Serialize` or boxed trait objects like //! `Box` because of Rust's ["object safety" //! rules](http://huonw.github.io/blog/2015/01/object-safety/). In particular, //! all three traits contain generic methods which cannot be made into a trait //! object. //! //! **The traits in this crate work seamlessly with any existing Serde //! `Serialize` and `Deserialize` type and any existing Serde `Serializer` and //! `Deserializer` format.** //! //! ## Serialization //! //! ```rust //! extern crate erased_serde; //! extern crate serde_json; //! extern crate serde_cbor; //! //! use std::collections::BTreeMap as Map; //! use std::io; //! //! use erased_serde::{Serialize, Serializer}; //! //! fn main() { //! // Construct some serializers. //! let json = &mut serde_json::ser::Serializer::new(io::stdout()); //! let cbor = &mut serde_cbor::ser::Serializer::new(io::stdout()); //! //! // The values in this map are boxed trait objects. Ordinarily this would not //! // be possible with serde::Serializer because of object safety, but type //! // erasure makes it possible with erased_serde::Serializer. //! let mut formats: Map<&str, Box> = Map::new(); //! formats.insert("json", Box::new(Serializer::erase(json))); //! formats.insert("cbor", Box::new(Serializer::erase(cbor))); //! //! // These are boxed trait objects as well. Same thing here - type erasure //! // makes this possible. //! let mut values: Map<&str, Box> = Map::new(); //! values.insert("vec", Box::new(vec!["a", "b"])); //! values.insert("int", Box::new(65536)); //! //! // Pick a Serializer out of the formats map. //! let format = formats.get_mut("json").unwrap(); //! //! // Pick a Serialize out of the values map. //! let value = values.get("vec").unwrap(); //! //! // This line prints `["a","b"]` to stdout. //! value.erased_serialize(format).unwrap(); //! } //! ``` //! //! ## Deserialization //! //! ```rust //! extern crate erased_serde; //! extern crate serde_json; //! extern crate serde_cbor; //! //! use std::collections::BTreeMap as Map; //! //! use erased_serde::Deserializer; //! //! fn main() { //! static JSON: &'static [u8] = br#"{"A": 65, "B": 66}"#; //! static CBOR: &'static [u8] = &[162, 97, 65, 24, 65, 97, 66, 24, 66]; //! //! // Construct some deserializers. //! let json = &mut serde_json::de::Deserializer::from_slice(JSON); //! let cbor = &mut serde_cbor::de::Deserializer::from_slice(CBOR); //! //! // The values in this map are boxed trait objects, which is not possible //! // with the normal serde::Deserializer because of object safety. //! let mut formats: Map<&str, Box> = Map::new(); //! formats.insert("json", Box::new(Deserializer::erase(json))); //! formats.insert("cbor", Box::new(Deserializer::erase(cbor))); //! //! // Pick a Deserializer out of the formats map. //! let format = formats.get_mut("json").unwrap(); //! //! let data: Map = erased_serde::deserialize(format).unwrap(); //! //! println!("{}", data["A"] + data["B"]); //! } //! ``` #![doc(html_root_url = "https://docs.rs/erased-serde/0.3.6")] #![cfg_attr(feature = "unstable-debug", feature(core_intrinsics))] #[macro_use] extern crate serde; #[cfg(test)] #[macro_use] extern crate serde_derive; #[cfg(test)] extern crate serde_json; #[macro_use] mod macros; mod any; mod de; mod error; mod ser; pub use de::{deserialize, Deserializer}; pub use error::Error; pub use ser::{serialize, Serialize, Serializer}; // Not public API. #[doc(hidden)] pub mod private; erased-serde-0.3.6/src/macros.rs010066400017500001750000000112151316523633400147350ustar0000000000000000/// Implement `serde::Serialize` for a trait object that has /// `erased_serde::Serialize` as a supertrait. /// /// ``` /// #[macro_use] /// extern crate erased_serde; /// /// trait Event: erased_serde::Serialize { /// /* ... */ /// } /// /// serialize_trait_object!(Event); /// # /// # fn main() {} /// ``` /// /// The macro supports traits that have type parameters and/or `where` clauses. /// /// ``` /// # #[macro_use] /// # extern crate erased_serde; /// # /// trait Difficult: erased_serde::Serialize where T: Copy { /// /* ... */ /// } /// /// serialize_trait_object!( Difficult where T: Copy); /// # /// # fn main() {} /// ``` #[macro_export] macro_rules! serialize_trait_object { ($($path:tt)+) => { __internal_serialize_trait_object!(begin $($path)+); }; } #[doc(hidden)] #[macro_export] macro_rules! __internal_serialize_trait_object { // Invocation started with `<`, parse generics. (begin < $($rest:tt)*) => { __internal_serialize_trait_object!(generics () () $($rest)*); }; // Invocation did not start with `<`. (begin $first:tt $($rest:tt)*) => { __internal_serialize_trait_object!(path () ($first) $($rest)*); }; // End of generics. (generics ($($generics:tt)*) () > $($rest:tt)*) => { __internal_serialize_trait_object!(path ($($generics)*) () $($rest)*); }; // Generics open bracket. (generics ($($generics:tt)*) ($($brackets:tt)*) < $($rest:tt)*) => { __internal_serialize_trait_object!(generics ($($generics)* <) ($($brackets)* <) $($rest)*); }; // Generics close bracket. (generics ($($generics:tt)*) (< $($brackets:tt)*) > $($rest:tt)*) => { __internal_serialize_trait_object!(generics ($($generics)* >) ($($brackets)*) $($rest)*); }; // Token inside of generics. (generics ($($generics:tt)*) ($($brackets:tt)*) $first:tt $($rest:tt)*) => { __internal_serialize_trait_object!(generics ($($generics)* $first) ($($brackets)*) $($rest)*); }; // End with `where` clause. (path ($($generics:tt)*) ($($path:tt)*) where $($rest:tt)*) => { __internal_serialize_trait_object!(sendsync ($($generics)*) ($($path)*) ($($rest)*)); }; // End without `where` clause. (path ($($generics:tt)*) ($($path:tt)*)) => { __internal_serialize_trait_object!(sendsync ($($generics)*) ($($path)*) ()); }; // Token inside of path. (path ($($generics:tt)*) ($($path:tt)*) $first:tt $($rest:tt)*) => { __internal_serialize_trait_object!(path ($($generics)*) ($($path)* $first) $($rest)*); }; // Expand into four impls. (sendsync ($($generics:tt)*) ($($path:tt)*) ($($bound:tt)*)) => { __internal_serialize_trait_object!(impl ($($generics)*) ($($path)*) ($($bound)*)); __internal_serialize_trait_object!(impl ($($generics)*) ($($path)* + $crate::private::Send) ($($bound)*)); __internal_serialize_trait_object!(impl ($($generics)*) ($($path)* + $crate::private::Sync) ($($bound)*)); __internal_serialize_trait_object!(impl ($($generics)*) ($($path)* + $crate::private::Send + $crate::private::Sync) ($($bound)*)); }; // The impl. (impl ($($generics:tt)*) ($($path:tt)*) ($($bound:tt)*)) => { impl<'erased, $($generics)*> $crate::private::serde::Serialize for $($path)* + 'erased where $($bound)* { fn serialize(&self, serializer: S) -> $crate::private::Result where S: $crate::private::serde::Serializer { $crate::serialize(self, serializer) } } }; } // TEST //////////////////////////////////////////////////////////////////////// #[cfg(test)] mod tests { use serde; use Serialize; fn assert_serialize() {} #[test] fn test_plain() { trait Trait: Serialize {} serialize_trait_object!(Trait); assert_serialize::(); assert_serialize::(); } #[test] fn test_type_parameter() { trait Trait: Serialize {} serialize_trait_object!( Trait); assert_serialize::>(); assert_serialize:: + Send>(); } #[test] fn test_generic_bound() { trait Trait, U>: Serialize {} serialize_trait_object!(, U> Trait); assert_serialize::>(); assert_serialize:: + Send>(); } #[test] fn test_where_clause() { trait Trait: Serialize where T: Clone {} serialize_trait_object!( Trait where T: Clone); assert_serialize::>(); assert_serialize:: + Send>(); } } erased-serde-0.3.6/src/private.rs010066400017500001750000000002211326675200600151170ustar0000000000000000//! Not public API. Used as `$crate::export` by macros. pub extern crate serde; pub use std::marker::{Send, Sync}; pub use std::result::Result; erased-serde-0.3.6/src/ser.rs010066400017500001750000001122021333713115100142300ustar0000000000000000use std::fmt::Display; use std::marker::PhantomData; use serde; use serde::ser::{SerializeSeq, SerializeTuple, SerializeTupleStruct, SerializeTupleVariant, SerializeMap, SerializeStruct, SerializeStructVariant}; use any::Any; use error::Error; // TRAITS ////////////////////////////////////////////////////////////////////// /// An object-safe equivalent of Serde's `Serialize` trait. /// /// Any implementation of Serde's `Serialize` converts seamlessly to an /// `&erased_serde::Serialize` or `Box` trait object. /// /// ```rust /// extern crate erased_serde; /// extern crate serde_json; /// extern crate serde_cbor; /// /// use std::collections::BTreeMap as Map; /// use std::io; /// /// use erased_serde::{Serialize, Serializer}; /// /// fn main() { /// // Construct some serializers. /// let json = &mut serde_json::ser::Serializer::new(io::stdout()); /// let cbor = &mut serde_cbor::ser::Serializer::new(io::stdout()); /// /// // The values in this map are boxed trait objects. Ordinarily this would not /// // be possible with serde::Serializer because of object safety, but type /// // erasure makes it possible with erased_serde::Serializer. /// let mut formats: Map<&str, Box> = Map::new(); /// formats.insert("json", Box::new(Serializer::erase(json))); /// formats.insert("cbor", Box::new(Serializer::erase(cbor))); /// /// // These are boxed trait objects as well. Same thing here - type erasure /// // makes this possible. /// let mut values: Map<&str, Box> = Map::new(); /// values.insert("vec", Box::new(vec!["a", "b"])); /// values.insert("int", Box::new(65536)); /// /// // Pick a Serializer out of the formats map. /// let format = formats.get_mut("json").unwrap(); /// /// // Pick a Serialize out of the values map. /// let value = values.get("vec").unwrap(); /// /// // This line prints `["a","b"]` to stdout. /// value.erased_serialize(format).unwrap(); /// } /// ``` pub trait Serialize { fn erased_serialize(&self, &mut Serializer) -> Result; } /// An object-safe equivalent of Serde's `Serializer` trait. /// /// Any implementation of Serde's `Serializer` can be converted to an /// `&erased_serde::Serializer` or `Box` trait object /// using `erased_serde::Serializer::erase`. /// /// ```rust /// extern crate erased_serde; /// extern crate serde_json; /// extern crate serde_cbor; /// /// use std::collections::BTreeMap as Map; /// use std::io; /// /// use erased_serde::{Serialize, Serializer}; /// /// fn main() { /// // Construct some serializers. /// let json = &mut serde_json::ser::Serializer::new(io::stdout()); /// let cbor = &mut serde_cbor::ser::Serializer::new(io::stdout()); /// /// // The values in this map are boxed trait objects. Ordinarily this would not /// // be possible with serde::Serializer because of object safety, but type /// // erasure makes it possible with erased_serde::Serializer. /// let mut formats: Map<&str, Box> = Map::new(); /// formats.insert("json", Box::new(Serializer::erase(json))); /// formats.insert("cbor", Box::new(Serializer::erase(cbor))); /// /// // These are boxed trait objects as well. Same thing here - type erasure /// // makes this possible. /// let mut values: Map<&str, Box> = Map::new(); /// values.insert("vec", Box::new(vec!["a", "b"])); /// values.insert("int", Box::new(65536)); /// /// // Pick a Serializer out of the formats map. /// let format = formats.get_mut("json").unwrap(); /// /// // Pick a Serialize out of the values map. /// let value = values.get("vec").unwrap(); /// /// // This line prints `["a","b"]` to stdout. /// value.erased_serialize(format).unwrap(); /// } /// ``` pub trait Serializer { fn erased_serialize_bool(&mut self, bool) -> Result; fn erased_serialize_i8(&mut self, i8) -> Result; fn erased_serialize_i16(&mut self, i16) -> Result; fn erased_serialize_i32(&mut self, i32) -> Result; fn erased_serialize_i64(&mut self, i64) -> Result; fn erased_serialize_u8(&mut self, u8) -> Result; fn erased_serialize_u16(&mut self, u16) -> Result; fn erased_serialize_u32(&mut self, u32) -> Result; fn erased_serialize_u64(&mut self, u64) -> Result; serde_if_integer128! { fn erased_serialize_i128(&mut self, i128) -> Result; fn erased_serialize_u128(&mut self, u128) -> Result; } fn erased_serialize_f32(&mut self, f32) -> Result; fn erased_serialize_f64(&mut self, f64) -> Result; fn erased_serialize_char(&mut self, char) -> Result; fn erased_serialize_str(&mut self, &str) -> Result; fn erased_serialize_bytes(&mut self, &[u8]) -> Result; fn erased_serialize_none(&mut self) -> Result; fn erased_serialize_some(&mut self, &Serialize) -> Result; fn erased_serialize_unit(&mut self) -> Result; fn erased_serialize_unit_struct(&mut self, name: &'static str) -> Result; fn erased_serialize_unit_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str) -> Result; fn erased_serialize_newtype_struct(&mut self, name: &'static str, &Serialize) -> Result; fn erased_serialize_newtype_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, &Serialize) -> Result; fn erased_serialize_seq(&mut self, len: Option) -> Result; fn erased_serialize_tuple(&mut self, len: usize) -> Result; fn erased_serialize_tuple_struct(&mut self, name: &'static str, len: usize) -> Result; fn erased_serialize_tuple_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, len: usize) -> Result; fn erased_serialize_map(&mut self, len: Option) -> Result; fn erased_serialize_struct(&mut self, name: &'static str, len: usize) -> Result; fn erased_serialize_struct_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, len: usize) -> Result; fn erased_is_human_readable(&self) -> bool; } impl Serializer { /// Convert any Serde `Serializer` to a trait object. /// /// ```rust /// extern crate erased_serde; /// extern crate serde_json; /// extern crate serde_cbor; /// /// use std::collections::BTreeMap as Map; /// use std::io; /// /// use erased_serde::{Serialize, Serializer}; /// /// fn main() { /// // Construct some serializers. /// let json = &mut serde_json::ser::Serializer::new(io::stdout()); /// let cbor = &mut serde_cbor::ser::Serializer::new(io::stdout()); /// /// // The values in this map are boxed trait objects. Ordinarily this would not /// // be possible with serde::Serializer because of object safety, but type /// // erasure makes it possible with erased_serde::Serializer. /// let mut formats: Map<&str, Box> = Map::new(); /// formats.insert("json", Box::new(Serializer::erase(json))); /// formats.insert("cbor", Box::new(Serializer::erase(cbor))); /// /// // These are boxed trait objects as well. Same thing here - type erasure /// // makes this possible. /// let mut values: Map<&str, Box> = Map::new(); /// values.insert("vec", Box::new(vec!["a", "b"])); /// values.insert("int", Box::new(65536)); /// /// // Pick a Serializer out of the formats map. /// let format = formats.get_mut("json").unwrap(); /// /// // Pick a Serialize out of the values map. /// let value = values.get("vec").unwrap(); /// /// // This line prints `["a","b"]` to stdout. /// value.erased_serialize(format).unwrap(); /// } /// ``` pub fn erase(serializer: S) -> erase::Serializer where S: serde::Serializer, S::Ok: 'static, { erase::Serializer { state: Some(serializer), } } } // OK ////////////////////////////////////////////////////////////////////////// // Corresponds to the Serializer::Ok associated type. // // This struct is exposed to users by invoking methods on the Serialize or // Serializer trait objects, so we need to make sure they do not hold on to the // Ok beyond the lifetime of the data in the Any. // // We do this by enforcing S::Ok is 'static for every Serializer trait object // created by the user. pub struct Ok { data: Any, } impl Ok { fn new(t: T) -> Self { Ok { data: Any::new(t), } } fn take(self) -> T { self.data.take() } } // IMPL ERASED SERDE FOR SERDE ///////////////////////////////////////////////// impl Serialize for T where T: serde::Serialize { fn erased_serialize(&self, serializer: &mut Serializer) -> Result { self.serialize(serializer) } } mod erase { pub struct Serializer { pub(crate) state: Option, } impl Serializer { pub(crate) fn take(&mut self) -> S { self.state.take().unwrap() } pub(crate) fn as_ref(&self) -> &S { self.state.as_ref().unwrap() } } } impl Serializer for erase::Serializer where T: serde::Serializer { fn erased_serialize_bool(&mut self, v: bool) -> Result { self.take().serialize_bool(v).map(Ok::new).map_err(erase) } fn erased_serialize_i8(&mut self, v: i8) -> Result { self.take().serialize_i8(v).map(Ok::new).map_err(erase) } fn erased_serialize_i16(&mut self, v: i16) -> Result { self.take().serialize_i16(v).map(Ok::new).map_err(erase) } fn erased_serialize_i32(&mut self, v: i32) -> Result { self.take().serialize_i32(v).map(Ok::new).map_err(erase) } fn erased_serialize_i64(&mut self, v: i64) -> Result { self.take().serialize_i64(v).map(Ok::new).map_err(erase) } fn erased_serialize_u8(&mut self, v: u8) -> Result { self.take().serialize_u8(v).map(Ok::new).map_err(erase) } fn erased_serialize_u16(&mut self, v: u16) -> Result { self.take().serialize_u16(v).map(Ok::new).map_err(erase) } fn erased_serialize_u32(&mut self, v: u32) -> Result { self.take().serialize_u32(v).map(Ok::new).map_err(erase) } fn erased_serialize_u64(&mut self, v: u64) -> Result { self.take().serialize_u64(v).map(Ok::new).map_err(erase) } serde_if_integer128! { fn erased_serialize_i128(&mut self, v: i128) -> Result { self.take().serialize_i128(v).map(Ok::new).map_err(erase) } fn erased_serialize_u128(&mut self, v: u128) -> Result { self.take().serialize_u128(v).map(Ok::new).map_err(erase) } } fn erased_serialize_f32(&mut self, v: f32) -> Result { self.take().serialize_f32(v).map(Ok::new).map_err(erase) } fn erased_serialize_f64(&mut self, v: f64) -> Result { self.take().serialize_f64(v).map(Ok::new).map_err(erase) } fn erased_serialize_char(&mut self, v: char) -> Result { self.take().serialize_char(v).map(Ok::new).map_err(erase) } fn erased_serialize_str(&mut self, v: &str) -> Result { self.take().serialize_str(v).map(Ok::new).map_err(erase) } fn erased_serialize_bytes(&mut self, v: &[u8]) -> Result { self.take().serialize_bytes(v).map(Ok::new).map_err(erase) } fn erased_serialize_none(&mut self) -> Result { self.take().serialize_none().map(Ok::new).map_err(erase) } fn erased_serialize_some(&mut self, v: &Serialize) -> Result { self.take().serialize_some(v).map(Ok::new).map_err(erase) } fn erased_serialize_unit(&mut self) -> Result { self.take().serialize_unit().map(Ok::new).map_err(erase) } fn erased_serialize_unit_struct(&mut self, name: &'static str) -> Result { self.take().serialize_unit_struct(name).map(Ok::new).map_err(erase) } fn erased_serialize_unit_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str) -> Result { self.take().serialize_unit_variant(name, variant_index, variant).map(Ok::new).map_err(erase) } fn erased_serialize_newtype_struct(&mut self, name: &'static str, v: &Serialize) -> Result { self.take().serialize_newtype_struct(name, v).map(Ok::new).map_err(erase) } fn erased_serialize_newtype_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, v: &Serialize) -> Result { self.take().serialize_newtype_variant(name, variant_index, variant, v).map(Ok::new).map_err(erase) } fn erased_serialize_seq(&mut self, len: Option) -> Result { self.take().serialize_seq(len).map(Seq::new).map_err(erase) } fn erased_serialize_tuple(&mut self, len: usize) -> Result { self.take().serialize_tuple(len).map(Tuple::new).map_err(erase) } fn erased_serialize_tuple_struct(&mut self, name: &'static str, len: usize) -> Result { self.take().serialize_tuple_struct(name, len).map(TupleStruct::new).map_err(erase) } fn erased_serialize_tuple_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, len: usize) -> Result { self.take().serialize_tuple_variant(name, variant_index, variant, len).map(TupleVariant::new).map_err(erase) } fn erased_serialize_map(&mut self, len: Option) -> Result { self.take().serialize_map(len).map(Map::new).map_err(erase) } fn erased_serialize_struct(&mut self, name: &'static str, len: usize) -> Result { self.take().serialize_struct(name, len).map(Struct::new).map_err(erase) } fn erased_serialize_struct_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, len: usize) -> Result { self.take().serialize_struct_variant(name, variant_index, variant, len).map(StructVariant::new).map_err(erase) } fn erased_is_human_readable(&self) -> bool { self.as_ref().is_human_readable() } } // IMPL SERDE FOR ERASED SERDE ///////////////////////////////////////////////// /// Serialize the given type-erased serializable value. /// /// This can be used to implement `serde::Serialize` for trait objects that have /// `erased_serde::Serialize` as a supertrait. /// /// ``` /// # extern crate serde; /// # extern crate erased_serde; /// # /// trait Event: erased_serde::Serialize { /// /* ... */ /// } /// /// impl<'a> serde::Serialize for Event + 'a { /// fn serialize(&self, serializer: S) -> Result /// where S: serde::Serializer /// { /// erased_serde::serialize(self, serializer) /// } /// } /// # /// # fn main() {} /// ``` /// /// Since this is reasonably common, the `serialize_trait_object!` macro /// generates such a Serialize impl. /// /// ``` /// #[macro_use] /// extern crate erased_serde; /// # /// # trait Event: erased_serde::Serialize {} /// /// serialize_trait_object!(Event); /// # /// # fn main() {} /// ``` pub fn serialize(value: &T, serializer: S) -> Result where T: Serialize, S: serde::Serializer { let mut erased = erase::Serializer { state: Some(serializer) }; value.erased_serialize(&mut erased).map(Ok::take).map_err(unerase) } serialize_trait_object!(Serialize); macro_rules! impl_serializer_for_trait_object { ($ty:ty) => { impl<'a> serde::Serializer for $ty { type Ok = Ok; type Error = Error; type SerializeSeq = Seq<'a>; type SerializeTuple = Tuple<'a>; type SerializeTupleStruct = TupleStruct<'a>; type SerializeTupleVariant = TupleVariant<'a>; type SerializeMap = Map<'a>; type SerializeStruct = Struct<'a>; type SerializeStructVariant = StructVariant<'a>; fn serialize_bool(self, v: bool) -> Result { self.erased_serialize_bool(v) } fn serialize_i8(self, v: i8) -> Result { self.erased_serialize_i8(v) } fn serialize_i16(self, v: i16) -> Result { self.erased_serialize_i16(v) } fn serialize_i32(self, v: i32) -> Result { self.erased_serialize_i32(v) } fn serialize_i64(self, v: i64) -> Result { self.erased_serialize_i64(v) } fn serialize_u8(self, v: u8) -> Result { self.erased_serialize_u8(v) } fn serialize_u16(self, v: u16) -> Result { self.erased_serialize_u16(v) } fn serialize_u32(self, v: u32) -> Result { self.erased_serialize_u32(v) } fn serialize_u64(self, v: u64) -> Result { self.erased_serialize_u64(v) } serde_if_integer128! { fn serialize_i128(self, v: i128) -> Result { self.erased_serialize_i128(v) } fn serialize_u128(self, v: u128) -> Result { self.erased_serialize_u128(v) } } fn serialize_f32(self, v: f32) -> Result { self.erased_serialize_f32(v) } fn serialize_f64(self, v: f64) -> Result { self.erased_serialize_f64(v) } fn serialize_char(self, v: char) -> Result { self.erased_serialize_char(v) } fn serialize_str(self, v: &str) -> Result { self.erased_serialize_str(v) } fn serialize_bytes(self, v: &[u8]) -> Result { self.erased_serialize_bytes(v) } fn serialize_none(self) -> Result { self.erased_serialize_none() } fn serialize_some(self, v: &T) -> Result { self.erased_serialize_some(&v) } fn serialize_unit(self) -> Result { self.erased_serialize_unit() } fn serialize_unit_struct(self, name: &'static str) -> Result { self.erased_serialize_unit_struct(name) } fn serialize_unit_variant(self, name: &'static str, variant_index: u32, variant: &'static str) -> Result { self.erased_serialize_unit_variant(name, variant_index, variant) } fn serialize_newtype_struct(self, name: &'static str, v: &T) -> Result { self.erased_serialize_newtype_struct(name, &v) } fn serialize_newtype_variant(self, name: &'static str, variant_index: u32, variant: &'static str, v: &T) -> Result { self.erased_serialize_newtype_variant(name, variant_index, variant, &v) } fn serialize_seq(self, len: Option) -> Result, Error> { self.erased_serialize_seq(len) } fn serialize_tuple(self, len: usize) -> Result, Error> { self.erased_serialize_tuple(len) } fn serialize_tuple_struct(self, name: &'static str, len: usize) -> Result, Error> { self.erased_serialize_tuple_struct(name, len) } fn serialize_tuple_variant(self, name: &'static str, variant_index: u32, variant: &'static str, len: usize) -> Result, Error> { self.erased_serialize_tuple_variant(name, variant_index, variant, len) } fn serialize_map(self, len: Option) -> Result, Error> { self.erased_serialize_map(len) } fn serialize_struct(self, name: &'static str, len: usize) -> Result, Error> { self.erased_serialize_struct(name, len) } fn serialize_struct_variant(self, name: &'static str, variant_index: u32, variant: &'static str, len: usize) -> Result, Error> { self.erased_serialize_struct_variant(name, variant_index, variant, len) } fn is_human_readable(&self) -> bool { self.erased_is_human_readable() } } }; } impl_serializer_for_trait_object!(&'a mut Serializer); impl_serializer_for_trait_object!(&'a mut (Serializer + Send)); impl_serializer_for_trait_object!(&'a mut (Serializer + Sync)); impl_serializer_for_trait_object!(&'a mut (Serializer + Send + Sync)); pub struct Seq<'a> { data: Any, serialize_element: fn(&mut Any, &Serialize) -> Result<(), Error>, end: fn(Any) -> Result, lifetime: PhantomData<&'a Serializer>, } impl<'a> Seq<'a> { fn new(data: T) -> Self { Seq { data: Any::new(data), serialize_element: |data, v| { data.view::().serialize_element(v).map_err(erase) }, end: |data| { data.take::().end().map(Ok::new).map_err(erase) }, lifetime: PhantomData, } } } impl<'a> SerializeSeq for Seq<'a> { type Ok = Ok; type Error = Error; fn serialize_element(&mut self, value: &T) -> Result<(), Error> where T: serde::Serialize { (self.serialize_element)(&mut self.data, &value) } fn end(self) -> Result { (self.end)(self.data) } } pub struct Tuple<'a> { data: Any, serialize_element: fn(&mut Any, &Serialize) -> Result<(), Error>, end: fn(Any) -> Result, lifetime: PhantomData<&'a Serializer>, } impl<'a> Tuple<'a> { fn new(data: T) -> Self { Tuple { data: Any::new(data), serialize_element: |data, v| { data.view::().serialize_element(v).map_err(erase) }, end: |data| { data.take::().end().map(Ok::new).map_err(erase) }, lifetime: PhantomData, } } } impl<'a> SerializeTuple for Tuple<'a> { type Ok = Ok; type Error = Error; fn serialize_element(&mut self, value: &T) -> Result<(), Error> where T: serde::Serialize { (self.serialize_element)(&mut self.data, &value) } fn end(self) -> Result { (self.end)(self.data) } } pub struct TupleStruct<'a> { data: Any, serialize_field: fn(&mut Any, &Serialize) -> Result<(), Error>, end: fn(Any) -> Result, lifetime: PhantomData<&'a Serializer>, } impl<'a> TupleStruct<'a> { fn new(data: T) -> Self { TupleStruct { data: Any::new(data), serialize_field: |data, v| { data.view::().serialize_field(v).map_err(erase) }, end: |data| { data.take::().end().map(Ok::new).map_err(erase) }, lifetime: PhantomData, } } } impl<'a> SerializeTupleStruct for TupleStruct<'a> { type Ok = Ok; type Error = Error; fn serialize_field(&mut self, value: &T) -> Result<(), Error> where T: serde::Serialize { (self.serialize_field)(&mut self.data, &value) } fn end(self) -> Result { (self.end)(self.data) } } pub struct TupleVariant<'a> { data: Any, serialize_field: fn(&mut Any, &Serialize) -> Result<(), Error>, end: fn(Any) -> Result, lifetime: PhantomData<&'a Serializer>, } impl<'a> TupleVariant<'a> { fn new(data: T) -> Self { TupleVariant { data: Any::new(data), serialize_field: |data, v| { data.view::().serialize_field(v).map_err(erase) }, end: |data| { data.take::().end().map(Ok::new).map_err(erase) }, lifetime: PhantomData, } } } impl<'a> SerializeTupleVariant for TupleVariant<'a> { type Ok = Ok; type Error = Error; fn serialize_field(&mut self, value: &T) -> Result<(), Error> where T: serde::Serialize { (self.serialize_field)(&mut self.data, &value) } fn end(self) -> Result { (self.end)(self.data) } } pub struct Map<'a> { data: Any, serialize_key: fn(&mut Any, &Serialize) -> Result<(), Error>, serialize_value: fn(&mut Any, &Serialize) -> Result<(), Error>, serialize_entry: fn(&mut Any, &Serialize, &Serialize) -> Result<(), Error>, end: fn(Any) -> Result, lifetime: PhantomData<&'a Serializer>, } impl<'a> Map<'a> { fn new(data: T) -> Self { Map { data: Any::new(data), serialize_key: |data, v| { data.view::().serialize_key(v).map_err(erase) }, serialize_value: |data, v| { data.view::().serialize_value(v).map_err(erase) }, serialize_entry: |data, k, v| { data.view::().serialize_entry(k, v).map_err(erase) }, end: |data| { data.take::().end().map(Ok::new).map_err(erase) }, lifetime: PhantomData, } } } impl<'a> SerializeMap for Map<'a> { type Ok = Ok; type Error = Error; fn serialize_key(&mut self, key: &T) -> Result<(), Error> where T: serde::Serialize { (self.serialize_key)(&mut self.data, &key) } fn serialize_value(&mut self, value: &T) -> Result<(), Error> where T: serde::Serialize { (self.serialize_value)(&mut self.data, &value) } fn serialize_entry(&mut self, key: &K, value: &V) -> Result<(), Error> where K: serde::Serialize, V: serde::Serialize { (self.serialize_entry)(&mut self.data, &key, &value) } fn end(self) -> Result { (self.end)(self.data) } } pub struct Struct<'a> { data: Any, serialize_field: fn(&mut Any, &'static str, &Serialize) -> Result<(), Error>, end: fn(Any) -> Result, lifetime: PhantomData<&'a Serializer>, } impl<'a> Struct<'a> { fn new(data: T) -> Self { Struct { data: Any::new(data), serialize_field: |data, k, v| { data.view::().serialize_field(k, v).map_err(erase) }, end: |data| { data.take::().end().map(Ok::new).map_err(erase) }, lifetime: PhantomData, } } } impl<'a> SerializeStruct for Struct<'a> { type Ok = Ok; type Error = Error; fn serialize_field(&mut self, name: &'static str, field: &T) -> Result<(), Error> where T: serde::Serialize { (self.serialize_field)(&mut self.data, name, &field) } fn end(self) -> Result { (self.end)(self.data) } } pub struct StructVariant<'a> { data: Any, serialize_field: fn(&mut Any, &'static str, &Serialize) -> Result<(), Error>, end: fn(Any) -> Result, lifetime: PhantomData<&'a Serializer>, } impl<'a> StructVariant<'a> { fn new(data: T) -> Self { StructVariant { data: Any::new(data), serialize_field: |data, k, v| { data.view::().serialize_field(k, v).map_err(erase) }, end: |data| { data.take::().end().map(Ok::new).map_err(erase) }, lifetime: PhantomData, } } } impl<'a> SerializeStructVariant for StructVariant<'a> { type Ok = Ok; type Error = Error; fn serialize_field(&mut self, name: &'static str, field: &T) -> Result<(), Error> where T: serde::Serialize { (self.serialize_field)(&mut self.data, name, &field) } fn end(self) -> Result { (self.end)(self.data) } } // IMPL ERASED SERDE FOR ERASED SERDE ////////////////////////////////////////// macro_rules! deref_erased_serializer { ($($imp:tt)+) => { impl $($imp)+ { fn erased_serialize_bool(&mut self, v: bool) -> Result { (**self).erased_serialize_bool(v) } fn erased_serialize_i8(&mut self, v: i8) -> Result { (**self).erased_serialize_i8(v) } fn erased_serialize_i16(&mut self, v: i16) -> Result { (**self).erased_serialize_i16(v) } fn erased_serialize_i32(&mut self, v: i32) -> Result { (**self).erased_serialize_i32(v) } fn erased_serialize_i64(&mut self, v: i64) -> Result { (**self).erased_serialize_i64(v) } fn erased_serialize_u8(&mut self, v: u8) -> Result { (**self).erased_serialize_u8(v) } fn erased_serialize_u16(&mut self, v: u16) -> Result { (**self).erased_serialize_u16(v) } fn erased_serialize_u32(&mut self, v: u32) -> Result { (**self).erased_serialize_u32(v) } fn erased_serialize_u64(&mut self, v: u64) -> Result { (**self).erased_serialize_u64(v) } serde_if_integer128! { fn erased_serialize_i128(&mut self, v: i128) -> Result { (**self).erased_serialize_i128(v) } fn erased_serialize_u128(&mut self, v: u128) -> Result { (**self).erased_serialize_u128(v) } } fn erased_serialize_f32(&mut self, v: f32) -> Result { (**self).erased_serialize_f32(v) } fn erased_serialize_f64(&mut self, v: f64) -> Result { (**self).erased_serialize_f64(v) } fn erased_serialize_char(&mut self, v: char) -> Result { (**self).erased_serialize_char(v) } fn erased_serialize_str(&mut self, v: &str) -> Result { (**self).erased_serialize_str(v) } fn erased_serialize_bytes(&mut self, v: &[u8]) -> Result { (**self).erased_serialize_bytes(v) } fn erased_serialize_none(&mut self) -> Result { (**self).erased_serialize_none() } fn erased_serialize_some(&mut self, v: &Serialize) -> Result { (**self).erased_serialize_some(v) } fn erased_serialize_unit(&mut self) -> Result { (**self).erased_serialize_unit() } fn erased_serialize_unit_struct(&mut self, name: &'static str) -> Result { (**self).erased_serialize_unit_struct(name) } fn erased_serialize_unit_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str) -> Result { (**self).erased_serialize_unit_variant(name, variant_index, variant) } fn erased_serialize_newtype_struct(&mut self, name: &'static str, v: &Serialize) -> Result { (**self).erased_serialize_newtype_struct(name, v) } fn erased_serialize_newtype_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, v: &Serialize) -> Result { (**self).erased_serialize_newtype_variant(name, variant_index, variant, v) } fn erased_serialize_seq(&mut self, len: Option) -> Result { (**self).erased_serialize_seq(len) } fn erased_serialize_tuple(&mut self, len: usize) -> Result { (**self).erased_serialize_tuple(len) } fn erased_serialize_tuple_struct(&mut self, name: &'static str, len: usize) -> Result { (**self).erased_serialize_tuple_struct(name, len) } fn erased_serialize_tuple_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, len: usize) -> Result { (**self).erased_serialize_tuple_variant(name, variant_index, variant, len) } fn erased_serialize_map(&mut self, len: Option) -> Result { (**self).erased_serialize_map(len) } fn erased_serialize_struct(&mut self, name: &'static str, len: usize) -> Result { (**self).erased_serialize_struct(name, len) } fn erased_serialize_struct_variant(&mut self, name: &'static str, variant_index: u32, variant: &'static str, len: usize) -> Result { (**self).erased_serialize_struct_variant(name, variant_index, variant, len) } fn erased_is_human_readable(&self) -> bool { (**self).erased_is_human_readable() } } }; } deref_erased_serializer!(<'a> Serializer for Box); deref_erased_serializer!(<'a> Serializer for Box); deref_erased_serializer!(<'a> Serializer for Box); deref_erased_serializer!(<'a> Serializer for Box); deref_erased_serializer!(<'a, T: ?Sized + Serializer> Serializer for &'a mut T); // ERROR /////////////////////////////////////////////////////////////////////// fn erase(e: E) -> Error where E: Display { serde::ser::Error::custom(e) } fn unerase(e: Error) -> E where E: serde::ser::Error { use std::error::Error; E::custom(e.description()) } // TEST //////////////////////////////////////////////////////////////////////// #[cfg(test)] mod tests { use super::*; use serde_json; fn test_json(t: T) where T: serde::Serialize { let expected = serde_json::to_vec(&t).unwrap(); // test borrowed trait object { let obj: &Serialize = &t; let mut buf = Vec::new(); { let mut ser = serde_json::Serializer::new(&mut buf); let ser: &mut Serializer = &mut Serializer::erase(&mut ser); obj.erased_serialize(ser).unwrap(); } assert_eq!(buf, expected); } // test boxed trait object { let obj: Box = Box::new(t); let mut buf = Vec::new(); { let mut ser = serde_json::Serializer::new(&mut buf); let mut ser: Box = Box::new(Serializer::erase(&mut ser)); obj.erased_serialize(&mut ser).unwrap(); } assert_eq!(buf, expected); } } #[test] fn test_vec() { test_json(vec!["a", "b"]); } #[test] fn test_struct() { #[derive(Serialize)] struct S { f: usize, } test_json(S { f: 256 }); } #[test] fn test_enum() { #[derive(Serialize)] enum E { Unit, Newtype(bool), Tuple(bool, bool), Struct { t: bool, f: bool }, } test_json(E::Unit); test_json(E::Newtype(true)); test_json(E::Tuple(true, false)); test_json(E::Struct { t: true, f: false }); } #[test] fn assert_serialize() { fn assert() {} assert::<&Serialize>(); assert::<&(Serialize + Send)>(); assert::<&(Serialize + Sync)>(); assert::<&(Serialize + Send + Sync)>(); assert::<&(Serialize + Sync + Send)>(); assert::>(); assert::>(); assert::>(); assert::>(); assert::>(); assert::>(); assert::>(); assert::>>(); assert::>>(); } #[test] fn assert_serializer() { fn assert() {} assert::<&mut Serializer>(); assert::<&mut (Serializer + Send)>(); assert::<&mut (Serializer + Sync)>(); assert::<&mut (Serializer + Send + Sync)>(); assert::<&mut (Serializer + Sync + Send)>(); } }