1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367
//! Generic serialization framework. #[cfg(feature = "std")] use std::error; #[cfg(not(feature = "std"))] use error; #[cfg(all(feature = "collections", not(feature = "std")))] use collections::String; pub mod impls; /////////////////////////////////////////////////////////////////////////////// /// `Error` is a trait that allows a `Serialize` to generically create a /// `Serializer` error. pub trait Error: Sized + error::Error { /// Raised when there is general error when deserializing a type. #[cfg(any(feature = "std", feature = "collections"))] fn custom<T: Into<String>>(msg: T) -> Self; /// Raised when there is general error when deserializing a type. #[cfg(all(not(feature = "std"), not(feature = "collections")))] fn custom<T: Into<&'static str>>(msg: T) -> Self; /// Raised when a `Serialize` was passed an incorrect value. fn invalid_value(msg: &str) -> Self { Error::custom(format!("invalid value: {}", msg)) } } /////////////////////////////////////////////////////////////////////////////// /// A trait that describes a type that can be serialized by a `Serializer`. pub trait Serialize { /// Serializes this value into this serializer. fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error> where S: Serializer; } /////////////////////////////////////////////////////////////////////////////// /// A trait that describes a type that can serialize a stream of values into the underlying format. pub trait Serializer { /// The error type that can be returned if some error occurs during serialization. type Error: Error; /// A state object that is initialized by `serialize_seq`, passed to /// `serialize_seq_elt`, and consumed by `serialize_seq_end`. Use `()` if no /// state is required. type SeqState; /// A state object that is initialized by `serialize_tuple`, passed to /// `serialize_tuple_elt`, and consumed by `serialize_tuple_end`. Use `()` /// if no state is required. type TupleState; /// A state object that is initialized by `serialize_tuple_struct`, passed /// to `serialize_tuple_struct_elt`, and consumed by /// `serialize_tuple_struct_end`. Use `()` if no state is required. type TupleStructState; /// A state object that is initialized by `serialize_tuple_variant`, passed /// to `serialize_tuple_variant_elt`, and consumed by /// `serialize_tuple_variant_end`. Use `()` if no state is required. type TupleVariantState; /// A state object that is initialized by `serialize_map`, passed to /// `serialize_map_elt`, and consumed by `serialize_map_end`. Use `()` if no /// state is required. type MapState; /// A state object that is initialized by `serialize_struct`, passed to /// `serialize_struct_elt`, and consumed by `serialize_struct_end`. Use `()` /// if no state is required. type StructState; /// A state object that is initialized by `serialize_struct_variant`, passed /// to `serialize_struct_variant_elt`, and consumed by /// `serialize_struct_variant_end`. Use `()` if no state is required. type StructVariantState; /// Serializes a `bool` value. fn serialize_bool(&mut self, v: bool) -> Result<(), Self::Error>; /// Serializes an `isize` value. If the format does not differentiate /// between `isize` and `i64`, a reasonable implementation would be to cast /// the value to `i64` and forward to `serialize_i64`. fn serialize_isize(&mut self, v: isize) -> Result<(), Self::Error>; /// Serializes an `i8` value. If the format does not differentiate between /// `i8` and `i64`, a reasonable implementation would be to cast the value /// to `i64` and forward to `serialize_i64`. fn serialize_i8(&mut self, v: i8) -> Result<(), Self::Error>; /// Serializes an `i16` value. If the format does not differentiate between /// `i16` and `i64`, a reasonable implementation would be to cast the value /// to `i64` and forward to `serialize_i64`. fn serialize_i16(&mut self, v: i16) -> Result<(), Self::Error>; /// Serializes an `i32` value. If the format does not differentiate between /// `i32` and `i64`, a reasonable implementation would be to cast the value /// to `i64` and forward to `serialize_i64`. fn serialize_i32(&mut self, v: i32) -> Result<(), Self::Error>; /// Serializes an `i64` value. fn serialize_i64(&mut self, v: i64) -> Result<(), Self::Error>; /// Serializes a `usize` value. If the format does not differentiate between /// `usize` and `u64`, a reasonable implementation would be to cast the /// value to `u64` and forward to `serialize_u64`. fn serialize_usize(&mut self, v: usize) -> Result<(), Self::Error>; /// Serializes a `u8` value. If the format does not differentiate between /// `u8` and `u64`, a reasonable implementation would be to cast the value /// to `u64` and forward to `serialize_u64`. fn serialize_u8(&mut self, v: u8) -> Result<(), Self::Error>; /// Serializes a `u16` value. If the format does not differentiate between /// `u16` and `u64`, a reasonable implementation would be to cast the value /// to `u64` and forward to `serialize_u64`. fn serialize_u16(&mut self, v: u16) -> Result<(), Self::Error>; /// Serializes a `u32` value. If the format does not differentiate between /// `u32` and `u64`, a reasonable implementation would be to cast the value /// to `u64` and forward to `serialize_u64`. fn serialize_u32(&mut self, v: u32) -> Result<(), Self::Error>; /// `Serializes a `u64` value. fn serialize_u64(&mut self, v: u64) -> Result<(), Self::Error>; /// Serializes an `f32` value. If the format does not differentiate between /// `f32` and `f64`, a reasonable implementation would be to cast the value /// to `f64` and forward to `serialize_f64`. fn serialize_f32(&mut self, v: f32) -> Result<(), Self::Error>; /// Serializes an `f64` value. fn serialize_f64(&mut self, v: f64) -> Result<(), Self::Error>; /// Serializes a character. fn serialize_char(&mut self, v: char) -> Result<(), Self::Error>; /// Serializes a `&str`. fn serialize_str(&mut self, value: &str) -> Result<(), Self::Error>; /// Enables serializers to serialize byte slices more compactly or more /// efficiently than other types of slices. If no efficient implementation /// is available, a reasonable implementation would be to forward to /// `serialize_seq`. fn serialize_bytes(&mut self, value: &[u8]) -> Result<(), Self::Error>; /// Serializes a `()` value. fn serialize_unit(&mut self) -> Result<(), Self::Error>; /// Serializes a unit struct value. A reasonable implementation would be to /// forward to `serialize_unit`. fn serialize_unit_struct( &mut self, name: &'static str, ) -> Result<(), Self::Error>; /// Serializes a unit variant, otherwise known as a variant with no /// arguments. A reasonable implementation would be to forward to /// `serialize_unit`. fn serialize_unit_variant( &mut self, name: &'static str, variant_index: usize, variant: &'static str, ) -> Result<(), Self::Error>; /// Allows a tuple struct with a single element, also known as a newtype /// struct, to be more efficiently serialized than a tuple struct with /// multiple items. A reasonable implementation would be to forward to /// `serialize_tuple_struct`. fn serialize_newtype_struct<T: Serialize>( &mut self, name: &'static str, value: T, ) -> Result<(), Self::Error>; /// Allows a variant with a single item to be more efficiently serialized /// than a variant with multiple items. A reasonable implementation would be /// to forward to `serialize_tuple_variant`. fn serialize_newtype_variant<T: Serialize>( &mut self, name: &'static str, variant_index: usize, variant: &'static str, value: T, ) -> Result<(), Self::Error>; /// Serializes a `None` value. fn serialize_none(&mut self) -> Result<(), Self::Error>; /// Serializes a `Some(...)` value. fn serialize_some<T: Serialize>( &mut self, value: T, ) -> Result<(), Self::Error>; /// Begins to serialize a sequence. This call must be followed by zero or /// more calls to `serialize_seq_elt`, then a call to `serialize_seq_end`. fn serialize_seq( &mut self, len: Option<usize>, ) -> Result<Self::SeqState, Self::Error>; /// Serializes a sequence element. Must have previously called /// `serialize_seq`. fn serialize_seq_elt<T: Serialize>( &mut self, state: &mut Self::SeqState, value: T, ) -> Result<(), Self::Error>; /// Finishes serializing a sequence. fn serialize_seq_end( &mut self, state: Self::SeqState, ) -> Result<(), Self::Error>; /// Begins to serialize a sequence whose length will be known at /// deserialization time. This call must be followed by zero or more calls /// to `serialize_seq_elt`, then a call to `serialize_seq_end`. A reasonable /// implementation would be to forward to `serialize_seq`. fn serialize_seq_fixed_size( &mut self, size: usize, ) -> Result<Self::SeqState, Self::Error>; /// Begins to serialize a tuple. This call must be followed by zero or more /// calls to `serialize_tuple_elt`, then a call to `serialize_tuple_end`. A /// reasonable implementation would be to forward to `serialize_seq`. fn serialize_tuple( &mut self, len: usize, ) -> Result<Self::TupleState, Self::Error>; /// Serializes a tuple element. Must have previously called /// `serialize_tuple`. fn serialize_tuple_elt<T: Serialize>( &mut self, state: &mut Self::TupleState, value: T, ) -> Result<(), Self::Error>; /// Finishes serializing a tuple. fn serialize_tuple_end( &mut self, state: Self::TupleState, ) -> Result<(), Self::Error>; /// Begins to serialize a tuple struct. This call must be followed by zero /// or more calls to `serialize_tuple_struct_elt`, then a call to /// `serialize_tuple_struct_end`. A reasonable implementation would be to /// forward to `serialize_tuple`. fn serialize_tuple_struct( &mut self, name: &'static str, len: usize, ) -> Result<Self::TupleStructState, Self::Error>; /// Serializes a tuple struct element. Must have previously called /// `serialize_tuple_struct`. fn serialize_tuple_struct_elt<T: Serialize>( &mut self, state: &mut Self::TupleStructState, value: T, ) -> Result<(), Self::Error>; /// Finishes serializing a tuple struct. fn serialize_tuple_struct_end( &mut self, state: Self::TupleStructState, ) -> Result<(), Self::Error>; /// Begins to serialize a tuple variant. This call must be followed by zero /// or more calls to `serialize_tuple_variant_elt`, then a call to /// `serialize_tuple_variant_end`. A reasonable implementation would be to /// forward to `serialize_tuple_struct`. fn serialize_tuple_variant( &mut self, name: &'static str, variant_index: usize, variant: &'static str, len: usize, ) -> Result<Self::TupleVariantState, Self::Error>; /// Serializes a tuple variant element. Must have previously called /// `serialize_tuple_variant`. fn serialize_tuple_variant_elt<T: Serialize>( &mut self, state: &mut Self::TupleVariantState, value: T, ) -> Result<(), Self::Error>; /// Finishes serializing a tuple variant. fn serialize_tuple_variant_end( &mut self, state: Self::TupleVariantState, ) -> Result<(), Self::Error>; /// Begins to serialize a map. This call must be followed by zero or more /// calls to `serialize_map_elt`, then a call to `serialize_map_end`. fn serialize_map( &mut self, len: Option<usize>, ) -> Result<Self::MapState, Self::Error>; /// Serialize a map element. Must have previously called `serialize_map`. fn serialize_map_elt<K: Serialize, V: Serialize>( &mut self, state: &mut Self::MapState, key: K, value: V, ) -> Result<(), Self::Error>; /// Finishes serializing a map. fn serialize_map_end( &mut self, state: Self::MapState, ) -> Result<(), Self::Error>; /// Begins to serialize a struct. This call must be followed by zero or more /// calls to `serialize_struct_elt`, then a call to `serialize_struct_end`. fn serialize_struct( &mut self, name: &'static str, len: usize, ) -> Result<Self::StructState, Self::Error>; /// Serializes a struct field. Must have previously called /// `serialize_struct`. fn serialize_struct_elt<V: Serialize>( &mut self, state: &mut Self::StructState, key: &'static str, value: V, ) -> Result<(), Self::Error>; /// Finishes serializing a struct. fn serialize_struct_end( &mut self, state: Self::StructState, ) -> Result<(), Self::Error>; /// Begins to serialize a struct variant. This call must be followed by zero /// or more calls to `serialize_struct_variant_elt`, then a call to /// `serialize_struct_variant_end`. fn serialize_struct_variant( &mut self, name: &'static str, variant_index: usize, variant: &'static str, len: usize, ) -> Result<Self::StructVariantState, Self::Error>; /// Serialize a struct variant element. Must have previously called /// `serialize_struct_variant`. fn serialize_struct_variant_elt<V: Serialize>( &mut self, state: &mut Self::StructVariantState, key: &'static str, value: V, ) -> Result<(), Self::Error>; /// Finishes serializing a struct variant. fn serialize_struct_variant_end( &mut self, state: Self::StructVariantState, ) -> Result<(), Self::Error>; }