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1026 lines
59 KiB
HTML
1026 lines
59 KiB
HTML
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<ol class="chapter"><li class="chapter-item expanded affix "><a href="index.html">chainerror</a></li><li class="chapter-item expanded "><a href="tutorial1.html"><strong aria-hidden="true">1.</strong> Simple String Errors</a></li><li class="chapter-item expanded "><a href="tutorial2.html"><strong aria-hidden="true">2.</strong> Simple Chained String Errors</a></li><li class="chapter-item expanded "><a href="tutorial3.html"><strong aria-hidden="true">3.</strong> Mapping Errors</a></li><li class="chapter-item expanded "><a href="tutorial4.html"><strong aria-hidden="true">4.</strong> More Information</a></li><li class="chapter-item expanded "><a href="tutorial5.html"><strong aria-hidden="true">5.</strong> The source() of Errors</a></li><li class="chapter-item expanded "><a href="tutorial6.html"><strong aria-hidden="true">6.</strong> Downcast the Errors</a></li><li class="chapter-item expanded "><a href="tutorial7.html" class="active"><strong aria-hidden="true">7.</strong> The root cause of all Errors</a></li><li class="chapter-item expanded "><a href="tutorial8.html"><strong aria-hidden="true">8.</strong> Finding an Error cause</a></li><li class="chapter-item expanded "><a href="tutorial9.html"><strong aria-hidden="true">9.</strong> Selective Error Handling</a></li><li class="chapter-item expanded "><a href="tutorial10.html"><strong aria-hidden="true">10.</strong> ErrorKind to the rescue</a></li><li class="chapter-item expanded "><a href="tutorial11.html"><strong aria-hidden="true">11.</strong> Debug for the ErrorKind</a></li><li class="chapter-item expanded "><a href="tutorial12.html"><strong aria-hidden="true">12.</strong> Deref for the ErrorKind</a></li><li class="chapter-item expanded "><a href="tutorial13.html"><strong aria-hidden="true">13.</strong> Writing a library</a></li><li class="chapter-item expanded "><a href="tutorial14.html"><strong aria-hidden="true">14.</strong> Going back to std</a></li><li class="chapter-item expanded affix "><a href="end.html">The End</a></li></ol>
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<main>
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<h1 id="the-root-cause-of-all-errors"><a class="header" href="#the-root-cause-of-all-errors">The root cause of all Errors</a></h1>
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<p><code>chainerror</code> also has some helper methods:</p>
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<pre><code class="language-rust ignore">fn is_chain<T: 'static + Display + Debug>(&self) -> bool
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fn downcast_chain_ref<T: 'static + Display + Debug>(&self) -> Option<&chainerror::Error<T>>
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fn downcast_chain_mut<T: 'static + Display + Debug>(&mut self) -> Option<&mut chainerror::Error<T>>
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fn root_cause(&self) -> Option<&(dyn Error + 'static)>
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fn find_cause<U: Error + 'static>(&self) -> Option<&U>
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fn find_chain_cause<U: Error + 'static>(&self) -> Option<&chainerror::Error<U>>
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fn kind<'a>(&'a self) -> &'a T</code></pre>
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<p>Using <code>downcast_chain_ref::<String>()</code> gives a <code>chainerror::Error<String></code>, which can be used
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to call <code>.find_cause::<io::Error>()</code>. </p>
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<pre><code class="language-rust ignore"> if let Some(s) = e.downcast_chain_ref::<String>() {
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if let Some(ioerror) = s.find_cause::<io::Error>() {</code></pre>
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<p>or to use <code>.root_cause()</code>, which of course can be of any type implementing <code>std::error::Error</code>.</p>
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<pre><code class="language-rust ignore"> if let Some(e) = s.root_cause() {</code></pre>
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<pre><pre class="playground"><code class="language-rust">#![allow(clippy::single_match)]
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#![allow(clippy::redundant_pattern_matching)]
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use chainerror::{Context as _, ErrorDown as _};
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use std::error::Error;
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use std::io;
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fn do_some_io() -> Result<(), Box<dyn Error + Send + Sync>> {
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Err(io::Error::from(io::ErrorKind::NotFound))?;
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Ok(())
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}
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fn func2() -> Result<(), Box<dyn Error + Send + Sync>> {
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let filename = "foo.txt";
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do_some_io().context(format!("Error reading '{}'", filename))?;
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Ok(())
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}
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fn func1() -> Result<(), Box<dyn Error + Send + Sync>> {
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func2().context("func1 error")?;
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Ok(())
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}
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fn main() -> Result<(), Box<dyn Error + Send + Sync>> {
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if let Err(e) = func1() {
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eprintln!("Error: {}", e);
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if let Some(s) = e.downcast_chain_ref::<String>() {
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if let Some(ioerror) = s.find_cause::<io::Error>() {
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eprintln!("caused by: std::io::Error: {}", ioerror);
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match ioerror.kind() {
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io::ErrorKind::NotFound => eprintln!("of kind: std::io::ErrorKind::NotFound"),
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_ => {}
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}
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}
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if let Some(e) = s.root_cause() {
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let ioerror = e.downcast_ref::<io::Error>().unwrap();
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eprintln!("The root cause was: std::io::Error: {:#?}", ioerror);
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}
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}
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std::process::exit(1);
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}
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Ok(())
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}
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<span class="boring">#[allow(dead_code)]
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</span><span class="boring">mod chainerror {
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</span><span class="boring">#![doc = include_str!("../README.md")]
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</span><span class="boring">#![deny(clippy::all)]
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</span><span class="boring">#![allow(clippy::needless_doctest_main)]
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</span><span class="boring">#![deny(missing_docs)]
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</span><span class="boring">
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</span><span class="boring">use std::any::TypeId;
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</span><span class="boring">use std::error::Error as StdError;
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</span><span class="boring">use std::fmt::{Debug, Display, Formatter};
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</span><span class="boring">use std::panic::Location;
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</span><span class="boring">
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</span><span class="boring">/// chains an inner error kind `T` with a causing error
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</span><span class="boring">pub struct Error<T> {
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</span><span class="boring"> occurrence: Option<String>,
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</span><span class="boring"> kind: T,
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</span><span class="boring"> error_cause: Option<Box<dyn StdError + 'static + Send + Sync>>,
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</span><span class="boring">}
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</span><span class="boring">
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</span><span class="boring">/// convenience type alias
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</span><span class="boring">pub type Result<O, E> = std::result::Result<O, Error<E>>;
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</span><span class="boring">
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</span><span class="boring">impl<T: 'static + Display + Debug> Error<T> {
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</span><span class="boring"> /// Use the `context()` or `map_context()` Result methods instead of calling this directly
|
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</span><span class="boring"> #[inline]
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</span><span class="boring"> pub fn new(
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</span><span class="boring"> kind: T,
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</span><span class="boring"> error_cause: Option<Box<dyn StdError + 'static + Send + Sync>>,
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</span><span class="boring"> occurrence: Option<String>,
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</span><span class="boring"> ) -> Self {
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</span><span class="boring"> Self {
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</span><span class="boring"> occurrence,
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</span><span class="boring"> kind,
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</span><span class="boring"> error_cause,
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</span><span class="boring"> }
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</span><span class="boring"> }
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</span><span class="boring">
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</span><span class="boring"> /// return the root cause of the error chain, if any exists
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</span><span class="boring"> pub fn root_cause(&self) -> Option<&(dyn StdError + 'static)> {
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</span><span class="boring"> self.iter().last()
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</span><span class="boring"> }
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</span><span class="boring">
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</span><span class="boring"> /// Find the first error cause of type U, if any exists
|
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</span><span class="boring"> ///
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</span><span class="boring"> /// # Examples
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</span><span class="boring"> ///
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</span><span class="boring"> /// ```rust
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</span><span class="boring"> /// use chainerror::Context as _;
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</span><span class="boring"> /// use chainerror::ErrorDown as _;
|
|
</span><span class="boring"> /// use std::error::Error;
|
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</span><span class="boring"> /// use std::io;
|
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</span><span class="boring"> ///
|
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</span><span class="boring"> /// fn do_some_io() -> Result<(), Box<dyn Error + Send + Sync>> {
|
|
</span><span class="boring"> /// Err(io::Error::from(io::ErrorKind::NotFound))?;
|
|
</span><span class="boring"> /// Ok(())
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> ///
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</span><span class="boring"> /// chainerror::str_context!(Func2Error);
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// fn func2() -> Result<(), Box<dyn Error + Send + Sync>> {
|
|
</span><span class="boring"> /// let filename = "foo.txt";
|
|
</span><span class="boring"> /// do_some_io().context(Func2Error(format!("Error reading '{}'", filename)))?;
|
|
</span><span class="boring"> /// Ok(())
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// chainerror::str_context!(Func1Error);
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// fn func1() -> Result<(), Box<dyn Error + Send + Sync>> {
|
|
</span><span class="boring"> /// func2().context(Func1Error::new("func1 error"))?;
|
|
</span><span class="boring"> /// Ok(())
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// if let Err(e) = func1() {
|
|
</span><span class="boring"> /// if let Some(f1err) = e.downcast_chain_ref::<Func1Error>() {
|
|
</span><span class="boring"> /// assert!(f1err.find_cause::<io::Error>().is_some());
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// assert!(f1err.find_chain_cause::<Func2Error>().is_some());
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> /// # else {
|
|
</span><span class="boring"> /// # panic!();
|
|
</span><span class="boring"> /// # }
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> /// # else {
|
|
</span><span class="boring"> /// # unreachable!();
|
|
</span><span class="boring"> /// # }
|
|
</span><span class="boring"> /// ```
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> pub fn find_cause<U: StdError + 'static>(&self) -> Option<&U> {
|
|
</span><span class="boring"> self.iter()
|
|
</span><span class="boring"> .filter_map(<dyn StdError>::downcast_ref::<U>)
|
|
</span><span class="boring"> .next()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> /// Find the first error cause of type [`Error<U>`](Error), if any exists
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// Same as `find_cause`, but hides the [`Error<U>`](Error) implementation internals
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// # Examples
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// ```rust
|
|
</span><span class="boring"> /// # chainerror::str_context!(FooError);
|
|
</span><span class="boring"> /// # let err = chainerror::Error::new(String::new(), None, None);
|
|
</span><span class="boring"> /// // Instead of writing
|
|
</span><span class="boring"> /// err.find_cause::<chainerror::Error<FooError>>();
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// // leave out the chainerror::Error<FooError> implementation detail
|
|
</span><span class="boring"> /// err.find_chain_cause::<FooError>();
|
|
</span><span class="boring"> /// ```
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> pub fn find_chain_cause<U: StdError + 'static>(&self) -> Option<&Error<U>> {
|
|
</span><span class="boring"> self.iter()
|
|
</span><span class="boring"> .filter_map(<dyn StdError>::downcast_ref::<Error<U>>)
|
|
</span><span class="boring"> .next()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> /// Find the first error cause of type [`Error<U>`](Error) or `U`, if any exists and return `U`
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// Same as `find_cause` and `find_chain_cause`, but hides the [`Error<U>`](Error) implementation internals
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// # Examples
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// ```rust
|
|
</span><span class="boring"> /// # chainerror::str_context!(FooErrorKind);
|
|
</span><span class="boring"> /// # let err = chainerror::Error::new(String::new(), None, None);
|
|
</span><span class="boring"> /// // Instead of writing
|
|
</span><span class="boring"> /// err.find_cause::<chainerror::Error<FooErrorKind>>();
|
|
</span><span class="boring"> /// // and/or
|
|
</span><span class="boring"> /// err.find_chain_cause::<FooErrorKind>();
|
|
</span><span class="boring"> /// // and/or
|
|
</span><span class="boring"> /// err.find_cause::<FooErrorKind>();
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// // leave out the chainerror::Error<FooErrorKind> implementation detail
|
|
</span><span class="boring"> /// err.find_kind_or_cause::<FooErrorKind>();
|
|
</span><span class="boring"> /// ```
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> pub fn find_kind_or_cause<U: StdError + 'static>(&self) -> Option<&U> {
|
|
</span><span class="boring"> self.iter()
|
|
</span><span class="boring"> .filter_map(|e| {
|
|
</span><span class="boring"> e.downcast_ref::<Error<U>>()
|
|
</span><span class="boring"> .map(|e| e.kind())
|
|
</span><span class="boring"> .or_else(|| e.downcast_ref::<U>())
|
|
</span><span class="boring"> })
|
|
</span><span class="boring"> .next()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> /// Return a reference to T of [`Error<T>`](Error)
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// # Examples
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// ```rust
|
|
</span><span class="boring"> /// use chainerror::Context as _;
|
|
</span><span class="boring"> /// use std::error::Error;
|
|
</span><span class="boring"> /// use std::io;
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// fn do_some_io() -> Result<(), Box<dyn Error + Send + Sync>> {
|
|
</span><span class="boring"> /// Err(io::Error::from(io::ErrorKind::NotFound))?;
|
|
</span><span class="boring"> /// Ok(())
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// chainerror::str_context!(Func2Error);
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// fn func2() -> Result<(), Box<dyn Error + Send + Sync>> {
|
|
</span><span class="boring"> /// let filename = "foo.txt";
|
|
</span><span class="boring"> /// do_some_io().context(Func2Error(format!("Error reading '{}'", filename)))?;
|
|
</span><span class="boring"> /// Ok(())
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// #[derive(Debug)]
|
|
</span><span class="boring"> /// enum Func1ErrorKind {
|
|
</span><span class="boring"> /// Func2,
|
|
</span><span class="boring"> /// IO(String),
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// /// impl ::std::fmt::Display for Func1ErrorKind {…}
|
|
</span><span class="boring"> /// # impl ::std::fmt::Display for Func1ErrorKind {
|
|
</span><span class="boring"> /// # fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
|
|
</span><span class="boring"> /// # match self {
|
|
</span><span class="boring"> /// # Func1ErrorKind::Func2 => write!(f, "func1 error calling func2"),
|
|
</span><span class="boring"> /// # Func1ErrorKind::IO(filename) => write!(f, "Error reading '{}'", filename),
|
|
</span><span class="boring"> /// # }
|
|
</span><span class="boring"> /// # }
|
|
</span><span class="boring"> /// # }
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// fn func1() -> chainerror::Result<(), Func1ErrorKind> {
|
|
</span><span class="boring"> /// func2().context(Func1ErrorKind::Func2)?;
|
|
</span><span class="boring"> /// do_some_io().context(Func1ErrorKind::IO("bar.txt".into()))?;
|
|
</span><span class="boring"> /// Ok(())
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// if let Err(e) = func1() {
|
|
</span><span class="boring"> /// match e.kind() {
|
|
</span><span class="boring"> /// Func1ErrorKind::Func2 => {}
|
|
</span><span class="boring"> /// Func1ErrorKind::IO(filename) => panic!(),
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> /// }
|
|
</span><span class="boring"> /// # else {
|
|
</span><span class="boring"> /// # unreachable!();
|
|
</span><span class="boring"> /// # }
|
|
</span><span class="boring"> /// ```
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> pub fn kind(&self) -> &T {
|
|
</span><span class="boring"> &self.kind
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> /// Returns an Iterator over all error causes/sources
|
|
</span><span class="boring"> ///
|
|
</span><span class="boring"> /// # Example
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> pub fn iter(&self) -> impl Iterator<Item = &(dyn StdError + 'static)> {
|
|
</span><span class="boring"> ErrorIter {
|
|
</span><span class="boring"> current: Some(self),
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">/// Convenience methods for `Result<>` to turn the error into a decorated [`Error`](Error)
|
|
</span><span class="boring">pub trait Context<O, E: Into<Box<dyn StdError + 'static + Send + Sync>>> {
|
|
</span><span class="boring"> /// Decorate the error with a `kind` of type `T` and the source `Location`
|
|
</span><span class="boring"> fn context<T: 'static + Display + Debug>(self, kind: T) -> std::result::Result<O, Error<T>>;
|
|
</span><span class="boring">
|
|
</span><span class="boring"> /// Decorate the error just with the source `Location`
|
|
</span><span class="boring"> fn annotate(self) -> std::result::Result<O, Error<AnnotatedError>>;
|
|
</span><span class="boring">
|
|
</span><span class="boring"> /// Decorate the `error` with a `kind` of type `T` produced with a `FnOnce(&error)` and the source `Location`
|
|
</span><span class="boring"> fn map_context<T: 'static + Display + Debug, F: FnOnce(&E) -> T>(
|
|
</span><span class="boring"> self,
|
|
</span><span class="boring"> op: F,
|
|
</span><span class="boring"> ) -> std::result::Result<O, Error<T>>;
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">/// Convenience type to just decorate the error with the source `Location`
|
|
</span><span class="boring">pub struct AnnotatedError(());
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl Display for AnnotatedError {
|
|
</span><span class="boring"> fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
|
|
</span><span class="boring"> write!(f, "(passed error)")
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl Debug for AnnotatedError {
|
|
</span><span class="boring"> fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
|
|
</span><span class="boring"> write!(f, "(passed error)")
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<O, E: Into<Box<dyn StdError + 'static + Send + Sync>>> Context<O, E>
|
|
</span><span class="boring"> for std::result::Result<O, E>
|
|
</span><span class="boring">{
|
|
</span><span class="boring"> #[track_caller]
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn context<T: 'static + Display + Debug>(self, kind: T) -> std::result::Result<O, Error<T>> {
|
|
</span><span class="boring"> match self {
|
|
</span><span class="boring"> Ok(t) => Ok(t),
|
|
</span><span class="boring"> Err(error_cause) => Err(Error::new(
|
|
</span><span class="boring"> kind,
|
|
</span><span class="boring"> Some(error_cause.into()),
|
|
</span><span class="boring"> Some(Location::caller().to_string()),
|
|
</span><span class="boring"> )),
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[track_caller]
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn annotate(self) -> std::result::Result<O, Error<AnnotatedError>> {
|
|
</span><span class="boring"> match self {
|
|
</span><span class="boring"> Ok(t) => Ok(t),
|
|
</span><span class="boring"> Err(error_cause) => Err(Error::new(
|
|
</span><span class="boring"> AnnotatedError(()),
|
|
</span><span class="boring"> Some(error_cause.into()),
|
|
</span><span class="boring"> Some(Location::caller().to_string()),
|
|
</span><span class="boring"> )),
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[track_caller]
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn map_context<T: 'static + Display + Debug, F: FnOnce(&E) -> T>(
|
|
</span><span class="boring"> self,
|
|
</span><span class="boring"> op: F,
|
|
</span><span class="boring"> ) -> std::result::Result<O, Error<T>> {
|
|
</span><span class="boring"> match self {
|
|
</span><span class="boring"> Ok(t) => Ok(t),
|
|
</span><span class="boring"> Err(error_cause) => {
|
|
</span><span class="boring"> let kind = op(&error_cause);
|
|
</span><span class="boring"> Err(Error::new(
|
|
</span><span class="boring"> kind,
|
|
</span><span class="boring"> Some(error_cause.into()),
|
|
</span><span class="boring"> Some(Location::caller().to_string()),
|
|
</span><span class="boring"> ))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">/// An iterator over all error causes/sources
|
|
</span><span class="boring">pub struct ErrorIter<'a> {
|
|
</span><span class="boring"> current: Option<&'a (dyn StdError + 'static)>,
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<'a> Iterator for ErrorIter<'a> {
|
|
</span><span class="boring"> type Item = &'a (dyn StdError + 'static);
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn next(&mut self) -> Option<Self::Item> {
|
|
</span><span class="boring"> let current = self.current;
|
|
</span><span class="boring"> self.current = self.current.and_then(StdError::source);
|
|
</span><span class="boring"> current
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<T: 'static + Display + Debug> std::ops::Deref for Error<T> {
|
|
</span><span class="boring"> type Target = T;
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn deref(&self) -> &Self::Target {
|
|
</span><span class="boring"> &self.kind
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">/// Convenience trait to hide the [`Error<T>`](Error) implementation internals
|
|
</span><span class="boring">pub trait ErrorDown {
|
|
</span><span class="boring"> /// Test if of type `Error<T>`
|
|
</span><span class="boring"> fn is_chain<T: 'static + Display + Debug>(&self) -> bool;
|
|
</span><span class="boring"> /// Downcast to a reference of `Error<T>`
|
|
</span><span class="boring"> fn downcast_chain_ref<T: 'static + Display + Debug>(&self) -> Option<&Error<T>>;
|
|
</span><span class="boring"> /// Downcast to a mutable reference of `Error<T>`
|
|
</span><span class="boring"> fn downcast_chain_mut<T: 'static + Display + Debug>(&mut self) -> Option<&mut Error<T>>;
|
|
</span><span class="boring"> /// Downcast to T of `Error<T>`
|
|
</span><span class="boring"> fn downcast_inner_ref<T: 'static + StdError>(&self) -> Option<&T>;
|
|
</span><span class="boring"> /// Downcast to T mutable reference of `Error<T>`
|
|
</span><span class="boring"> fn downcast_inner_mut<T: 'static + StdError>(&mut self) -> Option<&mut T>;
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<U: 'static + Display + Debug> ErrorDown for Error<U> {
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn is_chain<T: 'static + Display + Debug>(&self) -> bool {
|
|
</span><span class="boring"> TypeId::of::<T>() == TypeId::of::<U>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_chain_ref<T: 'static + Display + Debug>(&self) -> Option<&Error<T>> {
|
|
</span><span class="boring"> if self.is_chain::<T>() {
|
|
</span><span class="boring"> #[allow(clippy::cast_ptr_alignment)]
|
|
</span><span class="boring"> unsafe {
|
|
</span><span class="boring"> #[allow(trivial_casts)]
|
|
</span><span class="boring"> Some(*(self as *const dyn StdError as *const &Error<T>))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> } else {
|
|
</span><span class="boring"> None
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_chain_mut<T: 'static + Display + Debug>(&mut self) -> Option<&mut Error<T>> {
|
|
</span><span class="boring"> if self.is_chain::<T>() {
|
|
</span><span class="boring"> #[allow(clippy::cast_ptr_alignment)]
|
|
</span><span class="boring"> unsafe {
|
|
</span><span class="boring"> #[allow(trivial_casts)]
|
|
</span><span class="boring"> Some(&mut *(self as *mut dyn StdError as *mut &mut Error<T>))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> } else {
|
|
</span><span class="boring"> None
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_inner_ref<T: 'static + StdError>(&self) -> Option<&T> {
|
|
</span><span class="boring"> if self.is_chain::<T>() {
|
|
</span><span class="boring"> #[allow(clippy::cast_ptr_alignment)]
|
|
</span><span class="boring"> unsafe {
|
|
</span><span class="boring"> #[allow(trivial_casts)]
|
|
</span><span class="boring"> Some(&(*(self as *const dyn StdError as *const &Error<T>)).kind)
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> } else {
|
|
</span><span class="boring"> None
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_inner_mut<T: 'static + StdError>(&mut self) -> Option<&mut T> {
|
|
</span><span class="boring"> if self.is_chain::<T>() {
|
|
</span><span class="boring"> #[allow(clippy::cast_ptr_alignment)]
|
|
</span><span class="boring"> unsafe {
|
|
</span><span class="boring"> #[allow(trivial_casts)]
|
|
</span><span class="boring"> Some(&mut (*(self as *mut dyn StdError as *mut &mut Error<T>)).kind)
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> } else {
|
|
</span><span class="boring"> None
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl ErrorDown for dyn StdError + 'static {
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn is_chain<T: 'static + Display + Debug>(&self) -> bool {
|
|
</span><span class="boring"> self.is::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_chain_ref<T: 'static + Display + Debug>(&self) -> Option<&Error<T>> {
|
|
</span><span class="boring"> self.downcast_ref::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_chain_mut<T: 'static + Display + Debug>(&mut self) -> Option<&mut Error<T>> {
|
|
</span><span class="boring"> self.downcast_mut::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_inner_ref<T: 'static + StdError>(&self) -> Option<&T> {
|
|
</span><span class="boring"> self.downcast_ref::<T>()
|
|
</span><span class="boring"> .or_else(|| self.downcast_ref::<Error<T>>().map(|e| e.kind()))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_inner_mut<T: 'static + StdError>(&mut self) -> Option<&mut T> {
|
|
</span><span class="boring"> if self.is::<T>() {
|
|
</span><span class="boring"> return self.downcast_mut::<T>();
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> self.downcast_mut::<Error<T>>()
|
|
</span><span class="boring"> .and_then(|e| e.downcast_inner_mut::<T>())
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl ErrorDown for dyn StdError + 'static + Send {
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn is_chain<T: 'static + Display + Debug>(&self) -> bool {
|
|
</span><span class="boring"> self.is::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_chain_ref<T: 'static + Display + Debug>(&self) -> Option<&Error<T>> {
|
|
</span><span class="boring"> self.downcast_ref::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_chain_mut<T: 'static + Display + Debug>(&mut self) -> Option<&mut Error<T>> {
|
|
</span><span class="boring"> self.downcast_mut::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_inner_ref<T: 'static + StdError>(&self) -> Option<&T> {
|
|
</span><span class="boring"> self.downcast_ref::<T>()
|
|
</span><span class="boring"> .or_else(|| self.downcast_ref::<Error<T>>().map(|e| e.kind()))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_inner_mut<T: 'static + StdError>(&mut self) -> Option<&mut T> {
|
|
</span><span class="boring"> if self.is::<T>() {
|
|
</span><span class="boring"> return self.downcast_mut::<T>();
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> self.downcast_mut::<Error<T>>()
|
|
</span><span class="boring"> .and_then(|e| e.downcast_inner_mut::<T>())
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl ErrorDown for dyn StdError + 'static + Send + Sync {
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn is_chain<T: 'static + Display + Debug>(&self) -> bool {
|
|
</span><span class="boring"> self.is::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_chain_ref<T: 'static + Display + Debug>(&self) -> Option<&Error<T>> {
|
|
</span><span class="boring"> self.downcast_ref::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_chain_mut<T: 'static + Display + Debug>(&mut self) -> Option<&mut Error<T>> {
|
|
</span><span class="boring"> self.downcast_mut::<Error<T>>()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_inner_ref<T: 'static + StdError>(&self) -> Option<&T> {
|
|
</span><span class="boring"> self.downcast_ref::<T>()
|
|
</span><span class="boring"> .or_else(|| self.downcast_ref::<Error<T>>().map(|e| e.kind()))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn downcast_inner_mut<T: 'static + StdError>(&mut self) -> Option<&mut T> {
|
|
</span><span class="boring"> if self.is::<T>() {
|
|
</span><span class="boring"> return self.downcast_mut::<T>();
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> self.downcast_mut::<Error<T>>()
|
|
</span><span class="boring"> .and_then(|e| e.downcast_inner_mut::<T>())
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<T: 'static + Display + Debug> StdError for Error<T> {
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn source(&self) -> Option<&(dyn StdError + 'static)> {
|
|
</span><span class="boring"> self.error_cause
|
|
</span><span class="boring"> .as_ref()
|
|
</span><span class="boring"> .map(|e| e.as_ref() as &(dyn StdError + 'static))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<T: 'static + Display + Debug> StdError for &mut Error<T> {
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn source(&self) -> Option<&(dyn StdError + 'static)> {
|
|
</span><span class="boring"> self.error_cause
|
|
</span><span class="boring"> .as_ref()
|
|
</span><span class="boring"> .map(|e| e.as_ref() as &(dyn StdError + 'static))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<T: 'static + Display + Debug> Display for Error<T> {
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
|
|
</span><span class="boring"> write!(f, "{}", self.kind)?;
|
|
</span><span class="boring">
|
|
</span><span class="boring"> if f.alternate() {
|
|
</span><span class="boring"> if let Some(e) = self.source() {
|
|
</span><span class="boring"> write!(f, "\nCaused by:\n {:#}", &e)?;
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> Ok(())
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<T: 'static + Display + Debug> Debug for Error<T> {
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
|
|
</span><span class="boring"> if f.alternate() {
|
|
</span><span class="boring"> let mut f = f.debug_struct(&format!("Error<{}>", std::any::type_name::<T>()));
|
|
</span><span class="boring">
|
|
</span><span class="boring"> let f = f
|
|
</span><span class="boring"> .field("occurrence", &self.occurrence)
|
|
</span><span class="boring"> .field("kind", &self.kind)
|
|
</span><span class="boring"> .field("source", &self.source());
|
|
</span><span class="boring">
|
|
</span><span class="boring"> f.finish()
|
|
</span><span class="boring"> } else {
|
|
</span><span class="boring"> if let Some(ref o) = self.occurrence {
|
|
</span><span class="boring"> write!(f, "{}: ", o)?;
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> if TypeId::of::<String>() == TypeId::of::<T>()
|
|
</span><span class="boring"> || TypeId::of::<&str>() == TypeId::of::<T>()
|
|
</span><span class="boring"> {
|
|
</span><span class="boring"> Display::fmt(&self.kind, f)?;
|
|
</span><span class="boring"> } else {
|
|
</span><span class="boring"> Debug::fmt(&self.kind, f)?;
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> if let Some(e) = self.source() {
|
|
</span><span class="boring"> write!(f, "\nCaused by:\n{:?}", &e)?;
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> Ok(())
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">impl<T> From<T> for Error<T>
|
|
</span><span class="boring">where
|
|
</span><span class="boring"> T: 'static + Display + Debug,
|
|
</span><span class="boring">{
|
|
</span><span class="boring"> #[track_caller]
|
|
</span><span class="boring"> #[inline]
|
|
</span><span class="boring"> fn from(e: T) -> Error<T> {
|
|
</span><span class="boring"> Error::new(e, None, Some(Location::caller().to_string()))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">}
|
|
</span><span class="boring">/// Convenience macro to create a "new type" T(String) and implement Display + Debug for T
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// # Examples
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// ```rust
|
|
</span><span class="boring">/// # use chainerror::Context as _;
|
|
</span><span class="boring">/// # use chainerror::ErrorDown as _;
|
|
</span><span class="boring">/// # use std::error::Error;
|
|
</span><span class="boring">/// # use std::io;
|
|
</span><span class="boring">/// # use std::result::Result;
|
|
</span><span class="boring">/// # fn do_some_io() -> Result<(), Box<dyn Error + Send + Sync>> {
|
|
</span><span class="boring">/// # Err(io::Error::from(io::ErrorKind::NotFound))?;
|
|
</span><span class="boring">/// # Ok(())
|
|
</span><span class="boring">/// # }
|
|
</span><span class="boring">/// chainerror::str_context!(Func2Error);
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// fn func2() -> chainerror::Result<(), Func2Error> {
|
|
</span><span class="boring">/// let filename = "foo.txt";
|
|
</span><span class="boring">/// do_some_io().context(Func2Error(format!("Error reading '{}'", filename)))?;
|
|
</span><span class="boring">/// Ok(())
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// chainerror::str_context!(Func1Error);
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// fn func1() -> Result<(), Box<dyn Error>> {
|
|
</span><span class="boring">/// func2().context(Func1Error::new("func1 error"))?;
|
|
</span><span class="boring">/// Ok(())
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">/// # if let Err(e) = func1() {
|
|
</span><span class="boring">/// # if let Some(f1err) = e.downcast_chain_ref::<Func1Error>() {
|
|
</span><span class="boring">/// # assert!(f1err.find_cause::<chainerror::Error<Func2Error>>().is_some());
|
|
</span><span class="boring">/// # assert!(f1err.find_chain_cause::<Func2Error>().is_some());
|
|
</span><span class="boring">/// # } else {
|
|
</span><span class="boring">/// # panic!();
|
|
</span><span class="boring">/// # }
|
|
</span><span class="boring">/// # } else {
|
|
</span><span class="boring">/// # unreachable!();
|
|
</span><span class="boring">/// # }
|
|
</span><span class="boring">/// ```
|
|
</span><span class="boring">#[macro_export]
|
|
</span><span class="boring">macro_rules! str_context {
|
|
</span><span class="boring"> ($e:ident) => {
|
|
</span><span class="boring"> #[derive(Clone)]
|
|
</span><span class="boring"> pub struct $e(pub String);
|
|
</span><span class="boring"> impl $e {
|
|
</span><span class="boring"> pub fn new<S: Into<String>>(s: S) -> Self {
|
|
</span><span class="boring"> $e(s.into())
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> impl ::std::fmt::Display for $e {
|
|
</span><span class="boring"> fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
|
|
</span><span class="boring"> write!(f, "{}", self.0)
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> impl ::std::fmt::Debug for $e {
|
|
</span><span class="boring"> fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
|
|
</span><span class="boring"> write!(f, "{}({})", stringify!($e), self.0)
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> impl ::std::error::Error for $e {}
|
|
</span><span class="boring"> };
|
|
</span><span class="boring">}
|
|
</span><span class="boring">
|
|
</span><span class="boring">/// Derive an Error for an ErrorKind, which wraps a [`Error`](Error) and implements a `kind()` method
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// It basically hides [`Error`](Error) to the outside and only exposes the [`kind()`](Error::kind)
|
|
</span><span class="boring">/// method.
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// Error::kind() returns the ErrorKind
|
|
</span><span class="boring">/// Error::source() returns the parent error
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// # Examples
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// ```rust
|
|
</span><span class="boring">/// use chainerror::Context as _;
|
|
</span><span class="boring">/// use std::io;
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// fn do_some_io(_f: &str) -> std::result::Result<(), io::Error> {
|
|
</span><span class="boring">/// return Err(io::Error::from(io::ErrorKind::NotFound));
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// #[derive(Debug, Clone)]
|
|
</span><span class="boring">/// pub enum ErrorKind {
|
|
</span><span class="boring">/// IO(String),
|
|
</span><span class="boring">/// FatalError(String),
|
|
</span><span class="boring">/// Unknown,
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// chainerror::err_kind!(Error, ErrorKind);
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// impl std::fmt::Display for ErrorKind {
|
|
</span><span class="boring">/// fn fmt(&self, f: &mut ::std::fmt::Formatter) -> std::fmt::Result {
|
|
</span><span class="boring">/// match self {
|
|
</span><span class="boring">/// ErrorKind::FatalError(e) => write!(f, "fatal error {}", e),
|
|
</span><span class="boring">/// ErrorKind::Unknown => write!(f, "unknown error"),
|
|
</span><span class="boring">/// ErrorKind::IO(filename) => write!(f, "Error reading '{}'", filename),
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// impl ErrorKind {
|
|
</span><span class="boring">/// fn from_io_error(e: &io::Error, f: String) -> Self {
|
|
</span><span class="boring">/// match e.kind() {
|
|
</span><span class="boring">/// io::ErrorKind::BrokenPipe => panic!("Should not happen"),
|
|
</span><span class="boring">/// io::ErrorKind::ConnectionReset => {
|
|
</span><span class="boring">/// ErrorKind::FatalError(format!("While reading `{}`: {}", f, e))
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">/// _ => ErrorKind::IO(f),
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// impl From<&io::Error> for ErrorKind {
|
|
</span><span class="boring">/// fn from(e: &io::Error) -> Self {
|
|
</span><span class="boring">/// ErrorKind::IO(format!("{}", e))
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// pub fn func1() -> std::result::Result<(), Error> {
|
|
</span><span class="boring">/// let filename = "bar.txt";
|
|
</span><span class="boring">///
|
|
</span><span class="boring">/// do_some_io(filename).map_context(|e| ErrorKind::from_io_error(e, filename.into()))?;
|
|
</span><span class="boring">/// do_some_io(filename).map_context(|e| ErrorKind::IO(filename.into()))?;
|
|
</span><span class="boring">/// do_some_io(filename).map_context(|e| ErrorKind::from(e))?;
|
|
</span><span class="boring">/// Ok(())
|
|
</span><span class="boring">/// }
|
|
</span><span class="boring">/// ```
|
|
</span><span class="boring">#[macro_export]
|
|
</span><span class="boring">macro_rules! err_kind {
|
|
</span><span class="boring"> ($e:ident, $k:ident) => {
|
|
</span><span class="boring"> pub struct $e($crate::Error<$k>);
|
|
</span><span class="boring">
|
|
</span><span class="boring"> impl $e {
|
|
</span><span class="boring"> pub fn kind(&self) -> &$k {
|
|
</span><span class="boring"> self.0.kind()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> impl From<$k> for $e {
|
|
</span><span class="boring"> fn from(e: $k) -> Self {
|
|
</span><span class="boring"> $e($crate::Error::new(e, None, None))
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> impl From<$crate::Error<$k>> for $e {
|
|
</span><span class="boring"> fn from(e: $crate::Error<$k>) -> Self {
|
|
</span><span class="boring"> $e(e)
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> impl From<&$e> for $k
|
|
</span><span class="boring"> where
|
|
</span><span class="boring"> $k: Clone,
|
|
</span><span class="boring"> {
|
|
</span><span class="boring"> fn from(e: &$e) -> Self {
|
|
</span><span class="boring"> e.kind().clone()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> impl std::error::Error for $e {
|
|
</span><span class="boring"> fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
|
|
</span><span class="boring"> self.0.source()
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> impl std::fmt::Display for $e {
|
|
</span><span class="boring"> fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
|
|
</span><span class="boring"> std::fmt::Display::fmt(&self.0, f)
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring">
|
|
</span><span class="boring"> impl std::fmt::Debug for $e {
|
|
</span><span class="boring"> fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
|
|
</span><span class="boring"> std::fmt::Debug::fmt(&self.0, f)
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> }
|
|
</span><span class="boring"> };
|
|
</span><span class="boring">}
|
|
</span><span class="boring">}</span></code></pre></pre>
|
|
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|
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</div>
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</body>
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</html>
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