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diff --git a/vendor/displaydoc/README.md b/vendor/displaydoc/README.md deleted file mode 100644 index a609b0f2..00000000 --- a/vendor/displaydoc/README.md +++ /dev/null @@ -1,115 +0,0 @@ -derive(Display) /// `From<docs>` -=============== - -[](https://crates.io/crates/displaydoc) -[](https://docs.rs/displaydoc) - -This library provides a convenient derive macro for the standard library's -[`core::fmt::Display`] trait. - -[`core::fmt::Display`]: https://doc.rust-lang.org/std/fmt/trait.Display.html - -```toml -[dependencies] -displaydoc = "0.2" -``` - -*Compiler support: requires rustc 1.56+* - -<br> - -### Example - -*Demonstration alongside the [`Error`][std::error::Error] derive macro from [`thiserror`](https://docs.rs/thiserror/1.0.25/thiserror/index.html), -to propagate source locations from [`io::Error`][std::io::Error] with the `#[source]` attribute:* -```rust -use std::io; -use displaydoc::Display; -use thiserror::Error; - -#[derive(Display, Error, Debug)] -pub enum DataStoreError { - /// data store disconnected - Disconnect(#[source] io::Error), - /// the data for key `{0}` is not available - Redaction(String), - /// invalid header (expected {expected:?}, found {found:?}) - InvalidHeader { - expected: String, - found: String, - }, - /// unknown data store error - Unknown, -} - -let error = DataStoreError::Redaction("CLASSIFIED CONTENT".to_string()); -assert!("the data for key `CLASSIFIED CONTENT` is not available" == &format!("{}", error)); -``` -*Note that although [`io::Error`][std::io::Error] implements `Display`, we do not add it to the -generated message for `DataStoreError::Disconnect`, since it is already made available via -`#[source]`. See further context on avoiding duplication in error reports at the rust blog -[here](https://github.com/yaahc/blog.rust-lang.org/blob/master/posts/inside-rust/2021-05-15-What-the-error-handling-project-group-is-working-towards.md#duplicate-information-issue).* - -<br> - -### Details - -- A `fmt::Display` impl is generated for your enum if you provide - a docstring comment on each variant as shown above in the example. The - `Display` derive macro supports a shorthand for interpolating fields from - the error: - - `/// {var}` ⟶ `write!("{}", self.var)` - - `/// {0}` ⟶ `write!("{}", self.0)` - - `/// {var:?}` ⟶ `write!("{:?}", self.var)` - - `/// {0:?}` ⟶ `write!("{:?}", self.0)` -- This also works with structs and [generic types][crate::Display#generic-type-parameters]: -```rust -/// oh no, an error: {0} -#[derive(Display)] -pub struct Error<E>(pub E); - -let error: Error<&str> = Error("muahaha i am an error"); -assert!("oh no, an error: muahaha i am an error" == &format!("{}", error)); -``` - -- Two optional attributes can be added to your types next to the derive: - - - `#[ignore_extra_doc_attributes]` makes the macro ignore any doc - comment attributes (or `///` lines) after the first. Multi-line - comments using `///` are otherwise treated as an error, so use this - attribute or consider switching to block doc comments (`/** */`). - - - `#[prefix_enum_doc_attributes]` combines the doc comment message on - your enum itself with the messages for each variant, in the format - “enum: variant”. When added to an enum, the doc comment on the enum - becomes mandatory. When added to any other type, it has no effect. - -- In case you want to have an independent doc comment, the - `#[displaydoc("...")` atrribute may be used on the variant or struct to - override it. - -<br> - -### FAQ - -1. **Is this crate `no_std` compatible?** - * Yes! This crate implements the [`core::fmt::Display`] trait, not the [`std::fmt::Display`] trait, so it should work in `std` and `no_std` environments. Just add `default-features = false`. - -2. **Does this crate work with `Path` and `PathBuf` via the `Display` trait?** - * Yuuup. This crate uses @dtolnay's [autoref specialization technique](https://github.com/dtolnay/case-studies/blob/master/autoref-specialization/README.md) to add a special trait for types to get the display impl. It then specializes for `Path` and `PathBuf`, and when either of these types are found, it calls `self.display()` to get a `std::path::Display<'_>` type which can be used with the `Display` format specifier! - - -#### License - -<sup> -Licensed under either of <a href="LICENSE-APACHE">Apache License, Version -2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option. -</sup> - -<br> - -<sub> -Unless you explicitly state otherwise, any contribution intentionally submitted -for inclusion in this crate by you, as defined in the Apache-2.0 license, shall -be dual licensed as above, without any additional terms or conditions. -</sub> |