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+//! CBOR and serialization.
+//!
+//! # Usage
+//!
+//! Serde CBOR supports Rust 1.40 and up. Add this to your `Cargo.toml`:
+//! ```toml
+//! [dependencies]
+//! serde_cbor = "0.10"
+//! ```
+//!
+//! Storing and loading Rust types is easy and requires only
+//! minimal modifications to the program code.
+//!
+//! ```rust
+//! use serde_derive::{Deserialize, Serialize};
+//! use std::error::Error;
+//! use std::fs::File;
+//!
+//! // Types annotated with `Serialize` can be stored as CBOR.
+//! // To be able to load them again add `Deserialize`.
+//! #[derive(Debug, Serialize, Deserialize)]
+//! struct Mascot {
+//! name: String,
+//! species: String,
+//! year_of_birth: u32,
+//! }
+//!
+//! fn main() -> Result<(), Box<dyn Error>> {
+//! let ferris = Mascot {
+//! name: "Ferris".to_owned(),
+//! species: "crab".to_owned(),
+//! year_of_birth: 2015,
+//! };
+//!
+//! let ferris_file = File::create("examples/ferris.cbor")?;
+//! // Write Ferris to the given file.
+//! // Instead of a file you can use any type that implements `io::Write`
+//! // like a HTTP body, database connection etc.
+//! serde_cbor::to_writer(ferris_file, &ferris)?;
+//!
+//! let tux_file = File::open("examples/tux.cbor")?;
+//! // Load Tux from a file.
+//! // Serde CBOR performs roundtrip serialization meaning that
+//! // the data will not change in any way.
+//! let tux: Mascot = serde_cbor::from_reader(tux_file)?;
+//!
+//! println!("{:?}", tux);
+//! // prints: Mascot { name: "Tux", species: "penguin", year_of_birth: 1996 }
+//!
+//! Ok(())
+//! }
+//! ```
+//!
+//! There are a lot of options available to customize the format.
+//! To operate on untyped CBOR values have a look at the `Value` type.
+//!
+//! # Type-based Serialization and Deserialization
+//! Serde provides a mechanism for low boilerplate serialization & deserialization of values to and
+//! from CBOR via the serialization API. To be able to serialize a piece of data, it must implement
+//! the `serde::Serialize` trait. To be able to deserialize a piece of data, it must implement the
+//! `serde::Deserialize` trait. Serde provides an annotation to automatically generate the
+//! code for these traits: `#[derive(Serialize, Deserialize)]`.
+//!
+//! The CBOR API also provides an enum `serde_cbor::Value`.
+//!
+//! # Packed Encoding
+//! When serializing structs or enums in CBOR the keys or enum variant names will be serialized
+//! as string keys to a map. Especially in embedded environments this can increase the file
+//! size too much. In packed encoding all struct keys, as well as any enum variant that has no data,
+//! will be serialized as variable sized integers. The first 24 entries in any struct consume only a
+//! single byte! Packed encoding uses serde's preferred [externally tagged enum
+//! format](https://serde.rs/enum-representations.html) and therefore serializes enum variant names
+//! as string keys when that variant contains data. So, in the packed encoding example, `FirstVariant`
+//! encodes to a single byte, but encoding `SecondVariant` requires 16 bytes.
+//!
+//! To serialize a document in this format use `Serializer::new(writer).packed_format()` or
+//! the shorthand `ser::to_vec_packed`. The deserialization works without any changes.
+//!
+//! If you would like to omit the enum variant encoding for all variants, including ones that
+//! contain data, you can add `legacy_enums()` in addition to `packed_format()`, as can seen
+//! in the Serialize using minimal encoding example.
+//!
+//! # Self describing documents
+//! In some contexts different formats are used but there is no way to declare the format used
+//! out of band. For this reason CBOR has a magic number that may be added before any document.
+//! Self describing documents are created with `serializer.self_describe()`.
+//!
+//! # Examples
+//! Read a CBOR value that is known to be a map of string keys to string values and print it.
+//!
+//! ```rust
+//! use std::collections::BTreeMap;
+//! use serde_cbor::from_slice;
+//!
+//! let slice = b"\xa5aaaAabaBacaCadaDaeaE";
+//! let value: BTreeMap<String, String> = from_slice(slice).unwrap();
+//! println!("{:?}", value); // {"e": "E", "d": "D", "a": "A", "c": "C", "b": "B"}
+//! ```
+//!
+//! Read a general CBOR value with an unknown content.
+//!
+//! ```rust
+//! use serde_cbor::from_slice;
+//! use serde_cbor::value::Value;
+//!
+//! let slice = b"\x82\x01\xa1aaab";
+//! let value: Value = from_slice(slice).unwrap();
+//! println!("{:?}", value); // Array([U64(1), Object({String("a"): String("b")})])
+//! ```
+//!
+//! Serialize an object.
+//!
+//! ```rust
+//! use std::collections::BTreeMap;
+//! use serde_cbor::to_vec;
+//!
+//! let mut programming_languages = BTreeMap::new();
+//! programming_languages.insert("rust", vec!["safe", "concurrent", "fast"]);
+//! programming_languages.insert("python", vec!["powerful", "friendly", "open"]);
+//! programming_languages.insert("js", vec!["lightweight", "interpreted", "object-oriented"]);
+//! let encoded = to_vec(&programming_languages);
+//! assert_eq!(encoded.unwrap().len(), 103);
+//! ```
+//!
+//! Deserializing data in the middle of a slice
+//! ```
+//! # extern crate serde_cbor;
+//! use serde_cbor::Deserializer;
+//!
+//! # fn main() {
+//! let data: Vec<u8> = vec![
+//! 0x66, 0x66, 0x6f, 0x6f, 0x62, 0x61, 0x72, 0x66, 0x66, 0x6f, 0x6f, 0x62,
+//! 0x61, 0x72,
+//! ];
+//! let mut deserializer = Deserializer::from_slice(&data);
+//! let value: &str = serde::de::Deserialize::deserialize(&mut deserializer)
+//! .unwrap();
+//! let rest = &data[deserializer.byte_offset()..];
+//! assert_eq!(value, "foobar");
+//! assert_eq!(rest, &[0x66, 0x66, 0x6f, 0x6f, 0x62, 0x61, 0x72]);
+//! # }
+//! ```
+//!
+//! Serialize using packed encoding
+//!
+//! ```rust
+//! use serde_derive::{Deserialize, Serialize};
+//! use serde_cbor::ser::to_vec_packed;
+//! use WithTwoVariants::*;
+//!
+//! #[derive(Debug, Serialize, Deserialize)]
+//! enum WithTwoVariants {
+//! FirstVariant,
+//! SecondVariant(u8),
+//! }
+//!
+//! let cbor = to_vec_packed(&FirstVariant).unwrap();
+//! assert_eq!(cbor.len(), 1);
+//!
+//! let cbor = to_vec_packed(&SecondVariant(0)).unwrap();
+//! assert_eq!(cbor.len(), 16); // Includes 13 bytes of "SecondVariant"
+//! ```
+//!
+//! Serialize using minimal encoding
+//!
+//! ```rust
+//! use serde_derive::{Deserialize, Serialize};
+//! use serde_cbor::{Result, Serializer, ser::{self, IoWrite}};
+//! use WithTwoVariants::*;
+//!
+//! fn to_vec_minimal<T>(value: &T) -> Result<Vec<u8>>
+//! where
+//! T: serde::Serialize,
+//! {
+//! let mut vec = Vec::new();
+//! value.serialize(&mut Serializer::new(&mut IoWrite::new(&mut vec)).packed_format().legacy_enums())?;
+//! Ok(vec)
+//! }
+//!
+//! #[derive(Debug, Serialize, Deserialize)]
+//! enum WithTwoVariants {
+//! FirstVariant,
+//! SecondVariant(u8),
+//! }
+//!
+//! let cbor = to_vec_minimal(&FirstVariant).unwrap();
+//! assert_eq!(cbor.len(), 1);
+//!
+//! let cbor = to_vec_minimal(&SecondVariant(0)).unwrap();
+//! assert_eq!(cbor.len(), 3);
+//! ```
+//!
+//! # `no-std` support
+//!
+//! Serde CBOR supports building in a `no_std` context, use the following lines
+//! in your `Cargo.toml` dependencies:
+//! ``` toml
+//! [dependencies]
+//! serde = { version = "1.0", default-features = false }
+//! serde_cbor = { version = "0.10", default-features = false }
+//! ```
+//!
+//! Without the `std` feature the functions [from_reader], [from_slice], [to_vec], and [to_writer]
+//! are not exported. To export [from_slice] and [to_vec] enable the `alloc` feature. The `alloc`
+//! feature uses the [`alloc` library][alloc-lib] and requires at least version 1.36.0 of Rust.
+//!
+//! [alloc-lib]: https://doc.rust-lang.org/alloc/
+//!
+//! *Note*: to use derive macros in serde you will need to declare `serde`
+//! dependency like so:
+//! ``` toml
+//! serde = { version = "1.0", default-features = false, features = ["derive"] }
+//! ```
+//!
+//! Serialize an object with `no_std` and without `alloc`.
+//! ``` rust
+//! # #[macro_use] extern crate serde_derive;
+//! # fn main() -> Result<(), serde_cbor::Error> {
+//! use serde::Serialize;
+//! use serde_cbor::Serializer;
+//! use serde_cbor::ser::SliceWrite;
+//!
+//! #[derive(Serialize)]
+//! struct User {
+//! user_id: u32,
+//! password_hash: [u8; 4],
+//! }
+//!
+//! let mut buf = [0u8; 100];
+//! let writer = SliceWrite::new(&mut buf[..]);
+//! let mut ser = Serializer::new(writer);
+//! let user = User {
+//! user_id: 42,
+//! password_hash: [1, 2, 3, 4],
+//! };
+//! user.serialize(&mut ser)?;
+//! let writer = ser.into_inner();
+//! let size = writer.bytes_written();
+//! let expected = [
+//! 0xa2, 0x67, 0x75, 0x73, 0x65, 0x72, 0x5f, 0x69, 0x64, 0x18, 0x2a, 0x6d,
+//! 0x70, 0x61, 0x73, 0x73, 0x77, 0x6f, 0x72, 0x64, 0x5f, 0x68, 0x61, 0x73,
+//! 0x68, 0x84, 0x1, 0x2, 0x3, 0x4
+//! ];
+//! assert_eq!(&buf[..size], expected);
+//! # Ok(())
+//! # }
+//! ```
+//!
+//! Deserialize an object.
+//! ``` rust
+//! # #[macro_use] extern crate serde_derive;
+//! # fn main() -> Result<(), serde_cbor::Error> {
+//! #[derive(Debug, PartialEq, Deserialize)]
+//! struct User {
+//! user_id: u32,
+//! password_hash: [u8; 4],
+//! }
+//!
+//! let value = [
+//! 0xa2, 0x67, 0x75, 0x73, 0x65, 0x72, 0x5f, 0x69, 0x64, 0x18, 0x2a, 0x6d,
+//! 0x70, 0x61, 0x73, 0x73, 0x77, 0x6f, 0x72, 0x64, 0x5f, 0x68, 0x61, 0x73,
+//! 0x68, 0x84, 0x1, 0x2, 0x3, 0x4
+//! ];
+//!
+//! // from_slice_with_scratch will not alter input data, use it whenever you
+//! // borrow from somewhere else.
+//! // You will have to size your scratch according to the input data you
+//! // expect.
+//! use serde_cbor::de::from_slice_with_scratch;
+//! let mut scratch = [0u8; 32];
+//! let user: User = from_slice_with_scratch(&value[..], &mut scratch)?;
+//! assert_eq!(user, User {
+//! user_id: 42,
+//! password_hash: [1, 2, 3, 4],
+//! });
+//!
+//! let mut value = [
+//! 0xa2, 0x67, 0x75, 0x73, 0x65, 0x72, 0x5f, 0x69, 0x64, 0x18, 0x2a, 0x6d,
+//! 0x70, 0x61, 0x73, 0x73, 0x77, 0x6f, 0x72, 0x64, 0x5f, 0x68, 0x61, 0x73,
+//! 0x68, 0x84, 0x1, 0x2, 0x3, 0x4
+//! ];
+//!
+//! // from_mut_slice will move data around the input slice, you may only use it
+//! // on data you may own or can modify.
+//! use serde_cbor::de::from_mut_slice;
+//! let user: User = from_mut_slice(&mut value[..])?;
+//! assert_eq!(user, User {
+//! user_id: 42,
+//! password_hash: [1, 2, 3, 4],
+//! });
+//! # Ok(())
+//! # }
+//! ```
+//!
+//! # Limitations
+//!
+//! While Serde CBOR strives to support all features of Serde and CBOR
+//! there are a few limitations.
+//!
+//! * [Tags] are ignored during deserialization and can't be emitted during
+//! serialization. This is because Serde has no concept of tagged
+//! values. See:&nbsp;[#3]
+//! * Unknown [simple values] cause an `UnassignedCode` error.
+//! The simple values *False* and *True* are recognized and parsed as bool.
+//! *Null* and *Undefined* are both deserialized as *unit*.
+//! The *unit* type is serialized as *Null*. See:&nbsp;[#86]
+//! * [128-bit integers] can't be directly encoded in CBOR. If you need them
+//! store them as a byte string. See:&nbsp;[#77]
+//!
+//! [Tags]: https://tools.ietf.org/html/rfc7049#section-2.4.4
+//! [#3]: https://github.com/pyfisch/cbor/issues/3
+//! [simple values]: https://tools.ietf.org/html/rfc7049#section-3.5
+//! [#86]: https://github.com/pyfisch/cbor/issues/86
+//! [128-bit integers]: https://doc.rust-lang.org/std/primitive.u128.html
+//! [#77]: https://github.com/pyfisch/cbor/issues/77
+
+#![deny(missing_docs)]
+#![cfg_attr(not(feature = "std"), no_std)]
+
+// When we are running tests in no_std mode we need to explicitly link std, because `cargo test`
+// will not work without it.
+#[cfg(all(not(feature = "std"), test))]
+extern crate std;
+
+#[cfg(feature = "alloc")]
+extern crate alloc;
+
+pub mod de;
+pub mod error;
+mod read;
+pub mod ser;
+pub mod tags;
+mod write;
+
+#[cfg(feature = "std")]
+pub mod value;
+
+// Re-export the [items recommended by serde](https://serde.rs/conventions.html).
+#[doc(inline)]
+pub use crate::de::{Deserializer, StreamDeserializer};
+
+#[doc(inline)]
+pub use crate::error::{Error, Result};
+
+#[doc(inline)]
+pub use crate::ser::Serializer;
+
+// Convenience functions for serialization and deserialization.
+// These functions are only available in `std` mode.
+#[cfg(feature = "std")]
+#[doc(inline)]
+pub use crate::de::from_reader;
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[doc(inline)]
+pub use crate::de::from_slice;
+
+#[cfg(any(feature = "std", feature = "alloc"))]
+#[doc(inline)]
+pub use crate::ser::to_vec;
+
+#[cfg(feature = "std")]
+#[doc(inline)]
+pub use crate::ser::to_writer;
+
+// Re-export the value type like serde_json
+#[cfg(feature = "std")]
+#[doc(inline)]
+pub use crate::value::Value;