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    //! [![github]](https://github.com/dtolnay/thiserror)&ensp;[![crates-io]](https://crates.io/crates/thiserror)&ensp;[![docs-rs]](https://docs.rs/thiserror)
    //!
    //! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
    //! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust
    //! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logo=docs.rs
    //!
    //! <br>
    //!
    //! This library provides a convenient derive macro for the standard library's
    //! [`std::error::Error`] trait.
    //!
    //! [`std::error::Error`]: https://doc.rust-lang.org/std/error/trait.Error.html
    //!
    //! <br>
    //!
    //! # Example
    //!
    //! ```rust
    //! # use std::io;
    //! use thiserror::Error;
    //!
    //! #[derive(Error, Debug)]
    //! pub enum DataStoreError {
    //!     #[error("data store disconnected")]
    //!     Disconnect(#[from] io::Error),
    //!     #[error("the data for key `{0}` is not available")]
    //!     Redaction(String),
    //!     #[error("invalid header (expected {expected:?}, found {found:?})")]
    //!     InvalidHeader {
    //!         expected: String,
    //!         found: String,
    //!     },
    //!     #[error("unknown data store error")]
    //!     Unknown,
    //! }
    //! ```
    //!
    //! <br>
    //!
    //! # Details
    //!
    //! - Thiserror deliberately does not appear in your public API. You get the
    //!   same thing as if you had written an implementation of `std::error::Error`
    //!   by hand, and switching from handwritten impls to thiserror or vice versa
    //!   is not a breaking change.
    //!
    //! - Errors may be enums, structs with named fields, tuple structs, or unit
    //!   structs.
    //!
    //! - A `Display` impl is generated for your error if you provide
    //!   `#[error("...")]` messages on the struct or each variant of your enum, as
    //!   shown above in the example.
    //!
    //!   The messages support a shorthand for interpolating fields from the error.
    //!
    //!     - `#[error("{var}")]`&ensp;⟶&ensp;`write!("{}", self.var)`
    //!     - `#[error("{0}")]`&ensp;⟶&ensp;`write!("{}", self.0)`
    //!     - `#[error("{var:?}")]`&ensp;⟶&ensp;`write!("{:?}", self.var)`
    //!     - `#[error("{0:?}")]`&ensp;⟶&ensp;`write!("{:?}", self.0)`
    //!
    //!   These shorthands can be used together with any additional format args,
    //!   which may be arbitrary expressions. For example:
    //!
    //!   ```rust
    //!   # use std::i32;
    //!   # use thiserror::Error;
    //!   #
    //!   #[derive(Error, Debug)]
    //!   pub enum Error {
    //!       #[error("invalid rdo_lookahead_frames {0} (expected < {})", i32::MAX)]
    //!       InvalidLookahead(u32),
    //!   }
    //!   ```
    //!
    //!   If one of the additional expression arguments needs to refer to a field of
    //!   the struct or enum, then refer to named fields as `.var` and tuple fields
    //!   as `.0`.
    //!
    //!   ```rust
    //!   # use thiserror::Error;
    //!   #
    //!   # fn first_char(s: &String) -> char {
    //!   #     s.chars().next().unwrap()
    //!   # }
    //!   #
    //!   # #[derive(Debug)]
    //!   # struct Limits {
    //!   #     lo: usize,
    //!   #     hi: usize,
    //!   # }
    //!   #
    //!   #[derive(Error, Debug)]
    //!   pub enum Error {
    //!       #[error("first letter must be lowercase but was {:?}", first_char(.0))]
    //!       WrongCase(String),
    //!       #[error("invalid index {idx}, expected at least {} and at most {}", .limits.lo, .limits.hi)]
    //!       OutOfBounds { idx: usize, limits: Limits },
    //!   }
    //!   ```
    //!
    //! - A `From` impl is generated for each variant containing a `#[from]`
    //!   attribute.
    //!
    //!   Note that the variant must not contain any other fields beyond the source
    //!   error and possibly a backtrace. A backtrace is captured from within the
    //!   `From` impl if there is a field for it.
    //!
    //!   ```rust
    //!   # const IGNORE: &str = stringify! {
    //!   #[derive(Error, Debug)]
    //!   pub enum MyError {
    //!       Io {
    //!           #[from]
    //!           source: io::Error,
    //!           backtrace: Backtrace,
    //!       },
    //!   }
    //!   # };
    //!   ```
    //!
    //! - The Error trait's `source()` method is implemented to return whichever
    //!   field has a `#[source]` attribute or is named `source`, if any. This is
    //!   for identifying the underlying lower level error that caused your error.
    //!
    //!   The `#[from]` attribute always implies that the same field is `#[source]`,
    //!   so you don't ever need to specify both attributes.
    //!
    //!   Any error type that implements `std::error::Error` or dereferences to `dyn
    //!   std::error::Error` will work as a source.
    //!
    //!   ```rust
    //!   # use std::fmt::{self, Display};
    //!   # use thiserror::Error;
    //!   #
    //!   #[derive(Error, Debug)]
    //!   pub struct MyError {
    //!       msg: String,
    //!       #[source]  // optional if field name is `source`
    //!       source: anyhow::Error,
    //!   }
    //!   #
    //!   # impl Display for MyError {
    //!   #     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
    //!   #         unimplemented!()
    //!   #     }
    //!   # }
    //!   ```
    //!
    //! - The Error trait's `provide()` method is implemented to provide whichever
    //!   field has a type named `Backtrace`, if any, as a
    //!   `std::backtrace::Backtrace`.
    //!
    //!   ```rust
    //!   # const IGNORE: &str = stringify! {
    //!   use std::backtrace::Backtrace;
    //!
    //!   #[derive(Error, Debug)]
    //!   pub struct MyError {
    //!       msg: String,
    //!       backtrace: Backtrace,  // automatically detected
    //!   }
    //!   # };
    //!   ```
    //!
    //! - If a field is both a source (named `source`, or has `#[source]` or
    //!   `#[from]` attribute) *and* is marked `#[backtrace]`, then the Error
    //!   trait's `provide()` method is forwarded to the source's `provide` so that
    //!   both layers of the error share the same backtrace.
    //!
    //!   ```rust
    //!   # const IGNORE: &str = stringify! {
    //!   #[derive(Error, Debug)]
    //!   pub enum MyError {
    //!       Io {
    //!           #[backtrace]
    //!           source: io::Error,
    //!       },
    //!   }
    //!   # };
    //!   ```
    //!
    //! - Errors may use `error(transparent)` to forward the source and Display
    //!   methods straight through to an underlying error without adding an
    //!   additional message. This would be appropriate for enums that need an
    //!   "anything else" variant.
    //!
    //!   ```
    //!   # use thiserror::Error;
    //!   #
    //!   #[derive(Error, Debug)]
    //!   pub enum MyError {
    //!       # /*
    //!       ...
    //!       # */
    //!
    //!       #[error(transparent)]
    //!       Other(#[from] anyhow::Error),  // source and Display delegate to anyhow::Error
    //!   }
    //!   ```
    //!
    //!   Another use case is hiding implementation details of an error
    //!   representation behind an opaque error type, so that the representation is
    //!   able to evolve without breaking the crate's public API.
    //!
    //!   ```
    //!   # use thiserror::Error;
    //!   #
    //!   // PublicError is public, but opaque and easy to keep compatible.
    //!   #[derive(Error, Debug)]
    //!   #[error(transparent)]
    //!   pub struct PublicError(#[from] ErrorRepr);
    //!
    //!   impl PublicError {
    //!       // Accessors for anything we do want to expose publicly.
    //!   }
    //!
    //!   // Private and free to change across minor version of the crate.
    //!   #[derive(Error, Debug)]
    //!   enum ErrorRepr {
    //!       # /*
    //!       ...
    //!       # */
    //!   }
    //!   ```
    //!
    //! - See also the [`anyhow`] library for a convenient single error type to use
    //!   in application code.
    //!
    //!   [`anyhow`]: https://github.com/dtolnay/anyhow

    #![allow(
        // Clippy bug: https://github.com/rust-lang/rust-clippy/issues/7421
        clippy::doc_markdown,
        clippy::module_name_repetitions,
        clippy::return_self_not_must_use,
        clippy::wildcard_imports,
    )]
    #![cfg_attr(provide_any, feature(provide_any))]

    mod aserror;
    mod display;
    #[cfg(provide_any)]
    mod provide;

    pub use thiserror_impl::*;

    // Not public API.
    #[doc(hidden)]
    pub mod __private {
        pub use crate::aserror::AsDynError;
        pub use crate::display::{DisplayAsDisplay, PathAsDisplay};
        #[cfg(provide_any)]
        pub use crate::provide::ThiserrorProvide;
    }