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    //! # nom, eating data byte by byte
    //!
    //! nom is a parser combinator library with a focus on safe parsing,
    //! streaming patterns, and as much as possible zero copy.
    //!
    //! ## Example
    //!
    //! ```rust
    //! use nom::{
    //!   IResult,
    //!   bytes::complete::{tag, take_while_m_n},
    //!   combinator::map_res,
    //!   sequence::tuple};
    //!
    //! #[derive(Debug,PartialEq)]
    //! pub struct Color {
    //!   pub red:     u8,
    //!   pub green:   u8,
    //!   pub blue:    u8,
    //! }
    //!
    //! fn from_hex(input: &str) -> Result<u8, std::num::ParseIntError> {
    //!   u8::from_str_radix(input, 16)
    //! }
    //!
    //! fn is_hex_digit(c: char) -> bool {
    //!   c.is_digit(16)
    //! }
    //!
    //! fn hex_primary(input: &str) -> IResult<&str, u8> {
    //!   map_res(
    //!     take_while_m_n(2, 2, is_hex_digit),
    //!     from_hex
    //!   )(input)
    //! }
    //!
    //! fn hex_color(input: &str) -> IResult<&str, Color> {
    //!   let (input, _) = tag("#")(input)?;
    //!   let (input, (red, green, blue)) = tuple((hex_primary, hex_primary, hex_primary))(input)?;
    //!
    //!   Ok((input, Color { red, green, blue }))
    //! }
    //!
    //! fn main() {
    //!   assert_eq!(hex_color("#2F14DF"), Ok(("", Color {
    //!     red: 47,
    //!     green: 20,
    //!     blue: 223,
    //!   })));
    //! }
    //! ```
    //!
    //! The code is available on [Github](https://github.com/Geal/nom)
    //!
    //! There are a few [guides](https://github.com/Geal/nom/tree/main/doc) with more details
    //! about [how to write parsers](https://github.com/Geal/nom/blob/main/doc/making_a_new_parser_from_scratch.md),
    //! or the [error management system](https://github.com/Geal/nom/blob/main/doc/error_management.md).
    //! You can also check out the [recipes] module that contains examples of common patterns.
    //!
    //! **Looking for a specific combinator? Read the
    //! ["choose a combinator" guide](https://github.com/Geal/nom/blob/main/doc/choosing_a_combinator.md)**
    //!
    //! If you are upgrading to nom 5.0, please read the
    //! [migration document](https://github.com/Geal/nom/blob/main/doc/upgrading_to_nom_5.md).
    //!
    //! ## Parser combinators
    //!
    //! Parser combinators are an approach to parsers that is very different from
    //! software like [lex](https://en.wikipedia.org/wiki/Lex_(software)) and
    //! [yacc](https://en.wikipedia.org/wiki/Yacc). Instead of writing the grammar
    //! in a separate syntax and generating the corresponding code, you use very small
    //! functions with very specific purposes, like "take 5 bytes", or "recognize the
    //! word 'HTTP'", and assemble them in meaningful patterns like "recognize
    //! 'HTTP', then a space, then a version".
    //! The resulting code is small, and looks like the grammar you would have
    //! written with other parser approaches.
    //!
    //! This gives us a few advantages:
    //!
    //! - The parsers are small and easy to write
    //! - The parsers components are easy to reuse (if they're general enough, please add them to nom!)
    //! - The parsers components are easy to test separately (unit tests and property-based tests)
    //! - The parser combination code looks close to the grammar you would have written
    //! - You can build partial parsers, specific to the data you need at the moment, and ignore the rest
    //!
    //! Here is an example of one such parser, to recognize text between parentheses:
    //!
    //! ```rust
    //! use nom::{
    //!   IResult,
    //!   sequence::delimited,
    //!   // see the "streaming/complete" paragraph lower for an explanation of these submodules
    //!   character::complete::char,
    //!   bytes::complete::is_not
    //! };
    //!
    //! fn parens(input: &str) -> IResult<&str, &str> {
    //!   delimited(char('('), is_not(")"), char(')'))(input)
    //! }
    //! ```
    //!
    //! It defines a function named `parens` which will recognize a sequence of the
    //! character `(`, the longest byte array not containing `)`, then the character
    //! `)`, and will return the byte array in the middle.
    //!
    //! Here is another parser, written without using nom's combinators this time:
    //!
    //! ```rust
    //! use nom::{IResult, Err, Needed};
    //!
    //! # fn main() {
    //! fn take4(i: &[u8]) -> IResult<&[u8], &[u8]>{
    //!   if i.len() < 4 {
    //!     Err(Err::Incomplete(Needed::new(4)))
    //!   } else {
    //!     Ok((&i[4..], &i[0..4]))
    //!   }
    //! }
    //! # }
    //! ```
    //!
    //! This function takes a byte array as input, and tries to consume 4 bytes.
    //! Writing all the parsers manually, like this, is dangerous, despite Rust's
    //! safety features. There are still a lot of mistakes one can make. That's why
    //! nom provides a list of functions to help in developing parsers.
    //!
    //! With functions, you would write it like this:
    //!
    //! ```rust
    //! use nom::{IResult, bytes::streaming::take};
    //! fn take4(input: &str) -> IResult<&str, &str> {
    //!   take(4u8)(input)
    //! }
    //! ```
    //!
    //! A parser in nom is a function which, for an input type `I`, an output type `O`
    //! and an optional error type `E`, will have the following signature:
    //!
    //! ```rust,compile_fail
    //! fn parser(input: I) -> IResult<I, O, E>;
    //! ```
    //!
    //! Or like this, if you don't want to specify a custom error type (it will be `(I, ErrorKind)` by default):
    //!
    //! ```rust,compile_fail
    //! fn parser(input: I) -> IResult<I, O>;
    //! ```
    //!
    //! `IResult` is an alias for the `Result` type:
    //!
    //! ```rust
    //! use nom::{Needed, error::Error};
    //!
    //! type IResult<I, O, E = Error<I>> = Result<(I, O), Err<E>>;
    //!
    //! enum Err<E> {
    //!   Incomplete(Needed),
    //!   Error(E),
    //!   Failure(E),
    //! }
    //! ```
    //!
    //! It can have the following values:
    //!
    //! - A correct result `Ok((I,O))` with the first element being the remaining of the input (not parsed yet), and the second the output value;
    //! - An error `Err(Err::Error(c))` with `c` an error that can be built from the input position and a parser specific error
    //! - An error `Err(Err::Incomplete(Needed))` indicating that more input is necessary. `Needed` can indicate how much data is needed
    //! - An error `Err(Err::Failure(c))`. It works like the `Error` case, except it indicates an unrecoverable error: We cannot backtrack and test another parser
    //!
    //! Please refer to the ["choose a combinator" guide](https://github.com/Geal/nom/blob/main/doc/choosing_a_combinator.md) for an exhaustive list of parsers.
    //! See also the rest of the documentation [here](https://github.com/Geal/nom/blob/main/doc).
    //!
    //! ## Making new parsers with function combinators
    //!
    //! nom is based on functions that generate parsers, with a signature like
    //! this: `(arguments) -> impl Fn(Input) -> IResult<Input, Output, Error>`.
    //! The arguments of a combinator can be direct values (like `take` which uses
    //! a number of bytes or character as argument) or even other parsers (like
    //! `delimited` which takes as argument 3 parsers, and returns the result of
    //! the second one if all are successful).
    //!
    //! Here are some examples:
    //!
    //! ```rust
    //! use nom::IResult;
    //! use nom::bytes::complete::{tag, take};
    //! fn abcd_parser(i: &str) -> IResult<&str, &str> {
    //!   tag("abcd")(i) // will consume bytes if the input begins with "abcd"
    //! }
    //!
    //! fn take_10(i: &[u8]) -> IResult<&[u8], &[u8]> {
    //!   take(10u8)(i) // will consume and return 10 bytes of input
    //! }
    //! ```
    //!
    //! ## Combining parsers
    //!
    //! There are higher level patterns, like the **`alt`** combinator, which
    //! provides a choice between multiple parsers. If one branch fails, it tries
    //! the next, and returns the result of the first parser that succeeds:
    //!
    //! ```rust
    //! use nom::IResult;
    //! use nom::branch::alt;
    //! use nom::bytes::complete::tag;
    //!
    //! let mut alt_tags = alt((tag("abcd"), tag("efgh")));
    //!
    //! assert_eq!(alt_tags(&b"abcdxxx"[..]), Ok((&b"xxx"[..], &b"abcd"[..])));
    //! assert_eq!(alt_tags(&b"efghxxx"[..]), Ok((&b"xxx"[..], &b"efgh"[..])));
    //! assert_eq!(alt_tags(&b"ijklxxx"[..]), Err(nom::Err::Error((&b"ijklxxx"[..], nom::error::ErrorKind::Tag))));
    //! ```
    //!
    //! The **`opt`** combinator makes a parser optional. If the child parser returns
    //! an error, **`opt`** will still succeed and return None:
    //!
    //! ```rust
    //! use nom::{IResult, combinator::opt, bytes::complete::tag};
    //! fn abcd_opt(i: &[u8]) -> IResult<&[u8], Option<&[u8]>> {
    //!   opt(tag("abcd"))(i)
    //! }
    //!
    //! assert_eq!(abcd_opt(&b"abcdxxx"[..]), Ok((&b"xxx"[..], Some(&b"abcd"[..]))));
    //! assert_eq!(abcd_opt(&b"efghxxx"[..]), Ok((&b"efghxxx"[..], None)));
    //! ```
    //!
    //! **`many0`** applies a parser 0 or more times, and returns a vector of the aggregated results:
    //!
    //! ```rust
    //! # #[cfg(feature = "alloc")]
    //! # fn main() {
    //! use nom::{IResult, multi::many0, bytes::complete::tag};
    //! use std::str;
    //!
    //! fn multi(i: &str) -> IResult<&str, Vec<&str>> {
    //!   many0(tag("abcd"))(i)
    //! }
    //!
    //! let a = "abcdef";
    //! let b = "abcdabcdef";
    //! let c = "azerty";
    //! assert_eq!(multi(a), Ok(("ef",     vec!["abcd"])));
    //! assert_eq!(multi(b), Ok(("ef",     vec!["abcd", "abcd"])));
    //! assert_eq!(multi(c), Ok(("azerty", Vec::new())));
    //! # }
    //! # #[cfg(not(feature = "alloc"))]
    //! # fn main() {}
    //! ```
    //!
    //! Here are some basic combinators available:
    //!
    //! - **`opt`**: Will make the parser optional (if it returns the `O` type, the new parser returns `Option<O>`)
    //! - **`many0`**: Will apply the parser 0 or more times (if it returns the `O` type, the new parser returns `Vec<O>`)
    //! - **`many1`**: Will apply the parser 1 or more times
    //!
    //! There are more complex (and more useful) parsers like `tuple`, which is
    //! used to apply a series of parsers then assemble their results.
    //!
    //! Example with `tuple`:
    //!
    //! ```rust
    //! # fn main() {
    //! use nom::{error::ErrorKind, Needed,
    //! number::streaming::be_u16,
    //! bytes::streaming::{tag, take},
    //! sequence::tuple};
    //!
    //! let mut tpl = tuple((be_u16, take(3u8), tag("fg")));
    //!
    //! assert_eq!(
    //!   tpl(&b"abcdefgh"[..]),
    //!   Ok((
    //!     &b"h"[..],
    //!     (0x6162u16, &b"cde"[..], &b"fg"[..])
    //!   ))
    //! );
    //! assert_eq!(tpl(&b"abcde"[..]), Err(nom::Err::Incomplete(Needed::new(2))));
    //! let input = &b"abcdejk"[..];
    //! assert_eq!(tpl(input), Err(nom::Err::Error((&input[5..], ErrorKind::Tag))));
    //! # }
    //! ```
    //!
    //! But you can also use a sequence of combinators written in imperative style,
    //! thanks to the `?` operator:
    //!
    //! ```rust
    //! # fn main() {
    //! use nom::{IResult, bytes::complete::tag};
    //!
    //! #[derive(Debug, PartialEq)]
    //! struct A {
    //!   a: u8,
    //!   b: u8
    //! }
    //!
    //! fn ret_int1(i:&[u8]) -> IResult<&[u8], u8> { Ok((i,1)) }
    //! fn ret_int2(i:&[u8]) -> IResult<&[u8], u8> { Ok((i,2)) }
    //!
    //! fn f(i: &[u8]) -> IResult<&[u8], A> {
    //!   // if successful, the parser returns `Ok((remaining_input, output_value))` that we can destructure
    //!   let (i, _) = tag("abcd")(i)?;
    //!   let (i, a) = ret_int1(i)?;
    //!   let (i, _) = tag("efgh")(i)?;
    //!   let (i, b) = ret_int2(i)?;
    //!
    //!   Ok((i, A { a, b }))
    //! }
    //!
    //! let r = f(b"abcdefghX");
    //! assert_eq!(r, Ok((&b"X"[..], A{a: 1, b: 2})));
    //! # }
    //! ```
    //!
    //! ## Streaming / Complete
    //!
    //! Some of nom's modules have `streaming` or `complete` submodules. They hold
    //! different variants of the same combinators.
    //!
    //! A streaming parser assumes that we might not have all of the input data.
    //! This can happen with some network protocol or large file parsers, where the
    //! input buffer can be full and need to be resized or refilled.
    //!
    //! A complete parser assumes that we already have all of the input data.
    //! This will be the common case with small files that can be read entirely to
    //! memory.
    //!
    //! Here is how it works in practice:
    //!
    //! ```rust
    //! use nom::{IResult, Err, Needed, error::{Error, ErrorKind}, bytes, character};
    //!
    //! fn take_streaming(i: &[u8]) -> IResult<&[u8], &[u8]> {
    //!   bytes::streaming::take(4u8)(i)
    //! }
    //!
    //! fn take_complete(i: &[u8]) -> IResult<&[u8], &[u8]> {
    //!   bytes::complete::take(4u8)(i)
    //! }
    //!
    //! // both parsers will take 4 bytes as expected
    //! assert_eq!(take_streaming(&b"abcde"[..]), Ok((&b"e"[..], &b"abcd"[..])));
    //! assert_eq!(take_complete(&b"abcde"[..]), Ok((&b"e"[..], &b"abcd"[..])));
    //!
    //! // if the input is smaller than 4 bytes, the streaming parser
    //! // will return `Incomplete` to indicate that we need more data
    //! assert_eq!(take_streaming(&b"abc"[..]), Err(Err::Incomplete(Needed::new(1))));
    //!
    //! // but the complete parser will return an error
    //! assert_eq!(take_complete(&b"abc"[..]), Err(Err::Error(Error::new(&b"abc"[..], ErrorKind::Eof))));
    //!
    //! // the alpha0 function recognizes 0 or more alphabetic characters
    //! fn alpha0_streaming(i: &str) -> IResult<&str, &str> {
    //!   character::streaming::alpha0(i)
    //! }
    //!
    //! fn alpha0_complete(i: &str) -> IResult<&str, &str> {
    //!   character::complete::alpha0(i)
    //! }
    //!
    //! // if there's a clear limit to the recognized characters, both parsers work the same way
    //! assert_eq!(alpha0_streaming("abcd;"), Ok((";", "abcd")));
    //! assert_eq!(alpha0_complete("abcd;"), Ok((";", "abcd")));
    //!
    //! // but when there's no limit, the streaming version returns `Incomplete`, because it cannot
    //! // know if more input data should be recognized. The whole input could be "abcd;", or
    //! // "abcde;"
    //! assert_eq!(alpha0_streaming("abcd"), Err(Err::Incomplete(Needed::new(1))));
    //!
    //! // while the complete version knows that all of the data is there
    //! assert_eq!(alpha0_complete("abcd"), Ok(("", "abcd")));
    //! ```
    //! **Going further:** Read the [guides](https://github.com/Geal/nom/tree/main/doc),
    //! check out the [recipes]!
    #![cfg_attr(not(feature = "std"), no_std)]
    #![cfg_attr(feature = "cargo-clippy", allow(clippy::doc_markdown))]
    #![cfg_attr(feature = "docsrs", feature(doc_cfg))]
    #![cfg_attr(feature = "docsrs", feature(extended_key_value_attributes))]
    #![deny(missing_docs)]
    #[cfg_attr(nightly, warn(rustdoc::missing_doc_code_examples))]
    #[cfg(feature = "alloc")]
    #[macro_use]
    extern crate alloc;
    #[cfg(doctest)]
    extern crate doc_comment;

    #[cfg(doctest)]
    doc_comment::doctest!("../README.md");

    /// Lib module to re-export everything needed from `std` or `core`/`alloc`. This is how `serde` does
    /// it, albeit there it is not public.
    #[cfg_attr(nightly, allow(rustdoc::missing_doc_code_examples))]
    pub mod lib {
      /// `std` facade allowing `std`/`core` to be interchangeable. Reexports `alloc` crate optionally,
      /// as well as `core` or `std`
      #[cfg(not(feature = "std"))]
      #[cfg_attr(nightly, allow(rustdoc::missing_doc_code_examples))]
      /// internal std exports for no_std compatibility
      pub mod std {
        #[doc(hidden)]
        #[cfg(not(feature = "alloc"))]
        pub use core::borrow;

        #[cfg(feature = "alloc")]
        #[doc(hidden)]
        pub use alloc::{borrow, boxed, string, vec};

        #[doc(hidden)]
        pub use core::{cmp, convert, fmt, iter, mem, ops, option, result, slice, str};

        /// internal reproduction of std prelude
        #[doc(hidden)]
        pub mod prelude {
          pub use core::prelude as v1;
        }
      }

      #[cfg(feature = "std")]
      #[cfg_attr(nightly, allow(rustdoc::missing_doc_code_examples))]
      /// internal std exports for no_std compatibility
      pub mod std {
        #[doc(hidden)]
        pub use std::{
          alloc, borrow, boxed, cmp, collections, convert, fmt, hash, iter, mem, ops, option, result,
          slice, str, string, vec,
        };

        /// internal reproduction of std prelude
        #[doc(hidden)]
        pub mod prelude {
          pub use std::prelude as v1;
        }
      }
    }

    pub use self::bits::*;
    pub use self::internal::*;
    pub use self::traits::*;

    pub use self::str::*;

    #[macro_use]
    mod macros;
    #[macro_use]
    pub mod error;

    pub mod branch;
    pub mod combinator;
    mod internal;
    pub mod multi;
    pub mod sequence;
    mod traits;

    pub mod bits;
    pub mod bytes;

    pub mod character;

    mod str;

    pub mod number;

    #[cfg(feature = "docsrs")]
    #[cfg_attr(feature = "docsrs", cfg_attr(feature = "docsrs", doc = include_str!("../doc/nom_recipes.md")))]
    pub mod recipes {}