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    //! # Serde JSON
    //!
    //! JSON is a ubiquitous open-standard format that uses human-readable text to
    //! transmit data objects consisting of key-value pairs.
    //!
    //! ```json
    //! {
    //!     "name": "John Doe",
    //!     "age": 43,
    //!     "address": {
    //!         "street": "10 Downing Street",
    //!         "city": "London"
    //!     },
    //!     "phones": [
    //!         "+44 1234567",
    //!         "+44 2345678"
    //!     ]
    //! }
    //! ```
    //!
    //! There are three common ways that you might find yourself needing to work
    //! with JSON data in Rust.
    //!
    //!  - **As text data.** An unprocessed string of JSON data that you receive on
    //!    an HTTP endpoint, read from a file, or prepare to send to a remote
    //!    server.
    //!  - **As an untyped or loosely typed representation.** Maybe you want to
    //!    check that some JSON data is valid before passing it on, but without
    //!    knowing the structure of what it contains. Or you want to do very basic
    //!    manipulations like insert a key in a particular spot.
    //!  - **As a strongly typed Rust data structure.** When you expect all or most
    //!    of your data to conform to a particular structure and want to get real
    //!    work done without JSON's loosey-goosey nature tripping you up.
    //!
    //! Serde JSON provides efficient, flexible, safe ways of converting data
    //! between each of these representations.
    //!
    //! # Operating on untyped JSON values
    //!
    //! Any valid JSON data can be manipulated in the following recursive enum
    //! representation. This data structure is [`serde_json::Value`][value].
    //!
    //! ```
    //! # use serde_json::{Number, Map};
    //! #
    //! # #[allow(dead_code)]
    //! enum Value {
    //!     Null,
    //!     Bool(bool),
    //!     Number(Number),
    //!     String(String),
    //!     Array(Vec<Value>),
    //!     Object(Map<String, Value>),
    //! }
    //! ```
    //!
    //! A string of JSON data can be parsed into a `serde_json::Value` by the
    //! [`serde_json::from_str`][from_str] function. There is also
    //! [`from_slice`][from_slice] for parsing from a byte slice &[u8] and
    //! [`from_reader`][from_reader] for parsing from any `io::Read` like a File or
    //! a TCP stream.
    //!
    //! ```
    //! use serde_json::{Result, Value};
    //!
    //! fn untyped_example() -> Result<()> {
    //!     // Some JSON input data as a &str. Maybe this comes from the user.
    //!     let data = r#"
    //!         {
    //!             "name": "John Doe",
    //!             "age": 43,
    //!             "phones": [
    //!                 "+44 1234567",
    //!                 "+44 2345678"
    //!             ]
    //!         }"#;
    //!
    //!     // Parse the string of data into serde_json::Value.
    //!     let v: Value = serde_json::from_str(data)?;
    //!
    //!     // Access parts of the data by indexing with square brackets.
    //!     println!("Please call {} at the number {}", v["name"], v["phones"][0]);
    //!
    //!     Ok(())
    //! }
    //! #
    //! # fn main() {
    //! #     untyped_example().unwrap();
    //! # }
    //! ```
    //!
    //! The result of square bracket indexing like `v["name"]` is a borrow of the
    //! data at that index, so the type is `&Value`. A JSON map can be indexed with
    //! string keys, while a JSON array can be indexed with integer keys. If the
    //! type of the data is not right for the type with which it is being indexed,
    //! or if a map does not contain the key being indexed, or if the index into a
    //! vector is out of bounds, the returned element is `Value::Null`.
    //!
    //! When a `Value` is printed, it is printed as a JSON string. So in the code
    //! above, the output looks like `Please call "John Doe" at the number "+44
    //! 1234567"`. The quotation marks appear because `v["name"]` is a `&Value`
    //! containing a JSON string and its JSON representation is `"John Doe"`.
    //! Printing as a plain string without quotation marks involves converting from
    //! a JSON string to a Rust string with [`as_str()`] or avoiding the use of
    //! `Value` as described in the following section.
    //!
    //! [`as_str()`]: https://docs.serde.rs/serde_json/enum.Value.html#method.as_str
    //!
    //! The `Value` representation is sufficient for very basic tasks but can be
    //! tedious to work with for anything more significant. Error handling is
    //! verbose to implement correctly, for example imagine trying to detect the
    //! presence of unrecognized fields in the input data. The compiler is powerless
    //! to help you when you make a mistake, for example imagine typoing `v["name"]`
    //! as `v["nmae"]` in one of the dozens of places it is used in your code.
    //!
    //! # Parsing JSON as strongly typed data structures
    //!
    //! Serde provides a powerful way of mapping JSON data into Rust data structures
    //! largely automatically.
    //!
    //! ```
    //! use serde::{Deserialize, Serialize};
    //! use serde_json::Result;
    //!
    //! #[derive(Serialize, Deserialize)]
    //! struct Person {
    //!     name: String,
    //!     age: u8,
    //!     phones: Vec<String>,
    //! }
    //!
    //! fn typed_example() -> Result<()> {
    //!     // Some JSON input data as a &str. Maybe this comes from the user.
    //!     let data = r#"
    //!         {
    //!             "name": "John Doe",
    //!             "age": 43,
    //!             "phones": [
    //!                 "+44 1234567",
    //!                 "+44 2345678"
    //!             ]
    //!         }"#;
    //!
    //!     // Parse the string of data into a Person object. This is exactly the
    //!     // same function as the one that produced serde_json::Value above, but
    //!     // now we are asking it for a Person as output.
    //!     let p: Person = serde_json::from_str(data)?;
    //!
    //!     // Do things just like with any other Rust data structure.
    //!     println!("Please call {} at the number {}", p.name, p.phones[0]);
    //!
    //!     Ok(())
    //! }
    //! #
    //! # fn main() {
    //! #     typed_example().unwrap();
    //! # }
    //! ```
    //!
    //! This is the same `serde_json::from_str` function as before, but this time we
    //! assign the return value to a variable of type `Person` so Serde will
    //! automatically interpret the input data as a `Person` and produce informative
    //! error messages if the layout does not conform to what a `Person` is expected
    //! to look like.
    //!
    //! Any type that implements Serde's `Deserialize` trait can be deserialized
    //! this way. This includes built-in Rust standard library types like `Vec<T>`
    //! and `HashMap<K, V>`, as well as any structs or enums annotated with
    //! `#[derive(Deserialize)]`.
    //!
    //! Once we have `p` of type `Person`, our IDE and the Rust compiler can help us
    //! use it correctly like they do for any other Rust code. The IDE can
    //! autocomplete field names to prevent typos, which was impossible in the
    //! `serde_json::Value` representation. And the Rust compiler can check that
    //! when we write `p.phones[0]`, then `p.phones` is guaranteed to be a
    //! `Vec<String>` so indexing into it makes sense and produces a `String`.
    //!
    //! # Constructing JSON values
    //!
    //! Serde JSON provides a [`json!` macro][macro] to build `serde_json::Value`
    //! objects with very natural JSON syntax.
    //!
    //! ```
    //! use serde_json::json;
    //!
    //! fn main() {
    //!     // The type of `john` is `serde_json::Value`
    //!     let john = json!({
    //!         "name": "John Doe",
    //!         "age": 43,
    //!         "phones": [
    //!             "+44 1234567",
    //!             "+44 2345678"
    //!         ]
    //!     });
    //!
    //!     println!("first phone number: {}", john["phones"][0]);
    //!
    //!     // Convert to a string of JSON and print it out
    //!     println!("{}", john.to_string());
    //! }
    //! ```
    //!
    //! The `Value::to_string()` function converts a `serde_json::Value` into a
    //! `String` of JSON text.
    //!
    //! One neat thing about the `json!` macro is that variables and expressions can
    //! be interpolated directly into the JSON value as you are building it. Serde
    //! will check at compile time that the value you are interpolating is able to
    //! be represented as JSON.
    //!
    //! ```
    //! # use serde_json::json;
    //! #
    //! # fn random_phone() -> u16 { 0 }
    //! #
    //! let full_name = "John Doe";
    //! let age_last_year = 42;
    //!
    //! // The type of `john` is `serde_json::Value`
    //! let john = json!({
    //!     "name": full_name,
    //!     "age": age_last_year + 1,
    //!     "phones": [
    //!         format!("+44 {}", random_phone())
    //!     ]
    //! });
    //! ```
    //!
    //! This is amazingly convenient, but we have the problem we had before with
    //! `Value`: the IDE and Rust compiler cannot help us if we get it wrong. Serde
    //! JSON provides a better way of serializing strongly-typed data structures
    //! into JSON text.
    //!
    //! # Creating JSON by serializing data structures
    //!
    //! A data structure can be converted to a JSON string by
    //! [`serde_json::to_string`][to_string]. There is also
    //! [`serde_json::to_vec`][to_vec] which serializes to a `Vec<u8>` and
    //! [`serde_json::to_writer`][to_writer] which serializes to any `io::Write`
    //! such as a File or a TCP stream.
    //!
    //! ```
    //! use serde::{Deserialize, Serialize};
    //! use serde_json::Result;
    //!
    //! #[derive(Serialize, Deserialize)]
    //! struct Address {
    //!     street: String,
    //!     city: String,
    //! }
    //!
    //! fn print_an_address() -> Result<()> {
    //!     // Some data structure.
    //!     let address = Address {
    //!         street: "10 Downing Street".to_owned(),
    //!         city: "London".to_owned(),
    //!     };
    //!
    //!     // Serialize it to a JSON string.
    //!     let j = serde_json::to_string(&address)?;
    //!
    //!     // Print, write to a file, or send to an HTTP server.
    //!     println!("{}", j);
    //!
    //!     Ok(())
    //! }
    //! #
    //! # fn main() {
    //! #     print_an_address().unwrap();
    //! # }
    //! ```
    //!
    //! Any type that implements Serde's `Serialize` trait can be serialized this
    //! way. This includes built-in Rust standard library types like `Vec<T>` and
    //! `HashMap<K, V>`, as well as any structs or enums annotated with
    //! `#[derive(Serialize)]`.
    //!
    //! # No-std support
    //!
    //! As long as there is a memory allocator, it is possible to use serde_json
    //! without the rest of the Rust standard library. Disable the default "std"
    //! feature and enable the "alloc" feature:
    //!
    //! ```toml
    //! [dependencies]
    //! serde_json = { version = "1.0", default-features = false, features = ["alloc"] }
    //! ```
    //!
    //! For JSON support in Serde without a memory allocator, please see the
    //! [`serde-json-core`] crate.
    //!
    //! [value]: https://docs.serde.rs/serde_json/value/enum.Value.html
    //! [from_str]: https://docs.serde.rs/serde_json/de/fn.from_str.html
    //! [from_slice]: https://docs.serde.rs/serde_json/de/fn.from_slice.html
    //! [from_reader]: https://docs.serde.rs/serde_json/de/fn.from_reader.html
    //! [to_string]: https://docs.serde.rs/serde_json/ser/fn.to_string.html
    //! [to_vec]: https://docs.serde.rs/serde_json/ser/fn.to_vec.html
    //! [to_writer]: https://docs.serde.rs/serde_json/ser/fn.to_writer.html
    //! [macro]: https://docs.serde.rs/serde_json/macro.json.html
    //! [`serde-json-core`]: https://github.com/rust-embedded-community/serde-json-core

    #![doc(html_root_url = "https://docs.rs/serde_json/1.0.91")]
    // Ignored clippy lints
    #![allow(
        clippy::collapsible_else_if,
        clippy::comparison_chain,
        clippy::deprecated_cfg_attr,
        clippy::doc_markdown,
        clippy::excessive_precision,
        clippy::explicit_auto_deref,
        clippy::float_cmp,
        clippy::manual_range_contains,
        clippy::match_like_matches_macro,
        clippy::match_single_binding,
        clippy::needless_doctest_main,
        clippy::needless_late_init,
        // clippy bug: https://github.com/rust-lang/rust-clippy/issues/8366
        clippy::ptr_arg,
        clippy::return_self_not_must_use,
        clippy::transmute_ptr_to_ptr,
        clippy::unnecessary_wraps,
        // clippy bug: https://github.com/rust-lang/rust-clippy/issues/5704
        clippy::unnested_or_patterns,
    )]
    // Ignored clippy_pedantic lints
    #![allow(
        // buggy
        clippy::iter_not_returning_iterator, // https://github.com/rust-lang/rust-clippy/issues/8285
        // Deserializer::from_str, into_iter
        clippy::should_implement_trait,
        // integer and float ser/de requires these sorts of casts
        clippy::cast_possible_truncation,
        clippy::cast_possible_wrap,
        clippy::cast_precision_loss,
        clippy::cast_sign_loss,
        // correctly used
        clippy::enum_glob_use,
        clippy::if_not_else,
        clippy::integer_division,
        clippy::map_err_ignore,
        clippy::match_same_arms,
        clippy::similar_names,
        clippy::unused_self,
        clippy::wildcard_imports,
        // things are often more readable this way
        clippy::cast_lossless,
        clippy::module_name_repetitions,
        clippy::redundant_else,
        clippy::shadow_unrelated,
        clippy::single_match_else,
        clippy::too_many_lines,
        clippy::unreadable_literal,
        clippy::unseparated_literal_suffix,
        clippy::use_self,
        clippy::zero_prefixed_literal,
        // we support older compilers
        clippy::checked_conversions,
        clippy::mem_replace_with_default,
        // noisy
        clippy::missing_errors_doc,
        clippy::must_use_candidate,
    )]
    #![allow(non_upper_case_globals)]
    #![deny(missing_docs)]
    #![cfg_attr(not(feature = "std"), no_std)]
    #![cfg_attr(docsrs, feature(doc_cfg))]

    extern crate alloc;

    #[cfg(feature = "std")]
    #[doc(inline)]
    pub use crate::de::from_reader;
    #[doc(inline)]
    pub use crate::de::{from_slice, from_str, Deserializer, StreamDeserializer};
    #[doc(inline)]
    pub use crate::error::{Error, Result};
    #[doc(inline)]
    pub use crate::ser::{to_string, to_string_pretty, to_vec, to_vec_pretty};
    #[cfg(feature = "std")]
    #[doc(inline)]
    pub use crate::ser::{to_writer, to_writer_pretty, Serializer};
    #[doc(inline)]
    pub use crate::value::{from_value, to_value, Map, Number, Value};

    // We only use our own error type; no need for From conversions provided by the
    // standard library's try! macro. This reduces lines of LLVM IR by 4%.
    macro_rules! tri {
        ($e:expr $(,)?) => {
            match $e {
                core::result::Result::Ok(val) => val,
                core::result::Result::Err(err) => return core::result::Result::Err(err),
            }
        };
    }

    #[macro_use]
    mod macros;

    pub mod de;
    pub mod error;
    pub mod map;
    #[cfg(feature = "std")]
    #[cfg_attr(docsrs, doc(cfg(feature = "std")))]
    pub mod ser;
    #[cfg(not(feature = "std"))]
    mod ser;
    pub mod value;

    mod features_check;

    mod io;
    #[cfg(feature = "std")]
    mod iter;
    #[cfg(feature = "float_roundtrip")]
    mod lexical;
    mod number;
    mod read;

    #[cfg(feature = "raw_value")]
    mod raw;