diff options
Diffstat (limited to 'src/libstd/error.rs')
| -rw-r--r-- | src/libstd/error.rs | 160 |
1 files changed, 44 insertions, 116 deletions
diff --git a/src/libstd/error.rs b/src/libstd/error.rs index 0992e40121a..1407fe27715 100644 --- a/src/libstd/error.rs +++ b/src/libstd/error.rs @@ -45,92 +45,6 @@ use crate::string; /// [`source`]: trait.Error.html#method.source #[stable(feature = "rust1", since = "1.0.0")] pub trait Error: Debug + Display { - /// **This method is soft-deprecated.** - /// - /// Although using it won’t cause compilation warning, - /// new code should use [`Display`] instead - /// and new `impl`s can omit it. - /// - /// To obtain error description as a string, use `to_string()`. - /// - /// [`Display`]: ../fmt/trait.Display.html - /// - /// # Examples - /// - /// ``` - /// match "xc".parse::<u32>() { - /// Err(e) => { - /// // Print `e` itself, not `e.description()`. - /// println!("Error: {}", e); - /// } - /// _ => println!("No error"), - /// } - /// ``` - #[stable(feature = "rust1", since = "1.0.0")] - fn description(&self) -> &str { - "description() is deprecated; use Display" - } - - /// The lower-level cause of this error, if any. - /// - /// # Examples - /// - /// ``` - /// use std::error::Error; - /// use std::fmt; - /// - /// #[derive(Debug)] - /// struct SuperError { - /// side: SuperErrorSideKick, - /// } - /// - /// impl fmt::Display for SuperError { - /// fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - /// write!(f, "SuperError is here!") - /// } - /// } - /// - /// impl Error for SuperError { - /// fn cause(&self) -> Option<&dyn Error> { - /// Some(&self.side) - /// } - /// } - /// - /// #[derive(Debug)] - /// struct SuperErrorSideKick; - /// - /// impl fmt::Display for SuperErrorSideKick { - /// fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - /// write!(f, "SuperErrorSideKick is here!") - /// } - /// } - /// - /// impl Error for SuperErrorSideKick {} - /// - /// fn get_super_error() -> Result<(), SuperError> { - /// Err(SuperError { side: SuperErrorSideKick }) - /// } - /// - /// fn main() { - /// match get_super_error() { - /// Err(e) => { - /// println!("Error: {}", e.description()); - /// println!("Caused by: {}", e.cause().unwrap()); - /// } - /// _ => println!("No error"), - /// } - /// } - /// ``` - #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_deprecated( - since = "1.33.0", - reason = "replaced by Error::source, which can support \ - downcasting" - )] - fn cause(&self) -> Option<&dyn Error> { - self.source() - } - /// The lower-level source of this error, if any. /// /// # Examples @@ -213,6 +127,28 @@ pub trait Error: Debug + Display { fn backtrace(&self) -> Option<&Backtrace> { None } + + /// ``` + /// if let Err(e) = "xc".parse::<u32>() { + /// // Print `e` itself, no need for description(). + /// eprintln!("Error: {}", e); + /// } + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + #[rustc_deprecated(since = "1.41.0", reason = "use the Display impl or to_string()")] + fn description(&self) -> &str { + "description() is deprecated; use Display" + } + + #[stable(feature = "rust1", since = "1.0.0")] + #[rustc_deprecated( + since = "1.33.0", + reason = "replaced by Error::source, which can support downcasting" + )] + #[allow(missing_docs)] + fn cause(&self) -> Option<&dyn Error> { + self.source() + } } mod private { @@ -318,6 +254,7 @@ impl From<String> for Box<dyn Error + Send + Sync> { struct StringError(String); impl Error for StringError { + #[allow(deprecated)] fn description(&self) -> &str { &self.0 } @@ -454,47 +391,32 @@ impl<'a> From<Cow<'a, str>> for Box<dyn Error> { } #[unstable(feature = "never_type", issue = "35121")] -impl Error for ! { - fn description(&self) -> &str { - *self - } -} +impl Error for ! {} #[unstable( feature = "allocator_api", reason = "the precise API and guarantees it provides may be tweaked.", issue = "32838" )] -impl Error for AllocErr { - fn description(&self) -> &str { - "memory allocation failed" - } -} +impl Error for AllocErr {} #[unstable( feature = "allocator_api", reason = "the precise API and guarantees it provides may be tweaked.", issue = "32838" )] -impl Error for LayoutErr { - fn description(&self) -> &str { - "invalid parameters to Layout::from_size_align" - } -} +impl Error for LayoutErr {} #[unstable( feature = "allocator_api", reason = "the precise API and guarantees it provides may be tweaked.", issue = "32838" )] -impl Error for CannotReallocInPlace { - fn description(&self) -> &str { - CannotReallocInPlace::description(self) - } -} +impl Error for CannotReallocInPlace {} #[stable(feature = "rust1", since = "1.0.0")] impl Error for str::ParseBoolError { + #[allow(deprecated)] fn description(&self) -> &str { "failed to parse bool" } @@ -502,6 +424,7 @@ impl Error for str::ParseBoolError { #[stable(feature = "rust1", since = "1.0.0")] impl Error for str::Utf8Error { + #[allow(deprecated)] fn description(&self) -> &str { "invalid utf-8: corrupt contents" } @@ -509,6 +432,7 @@ impl Error for str::Utf8Error { #[stable(feature = "rust1", since = "1.0.0")] impl Error for num::ParseIntError { + #[allow(deprecated)] fn description(&self) -> &str { self.__description() } @@ -516,6 +440,7 @@ impl Error for num::ParseIntError { #[stable(feature = "try_from", since = "1.34.0")] impl Error for num::TryFromIntError { + #[allow(deprecated)] fn description(&self) -> &str { self.__description() } @@ -523,6 +448,7 @@ impl Error for num::TryFromIntError { #[stable(feature = "try_from", since = "1.34.0")] impl Error for array::TryFromSliceError { + #[allow(deprecated)] fn description(&self) -> &str { self.__description() } @@ -530,6 +456,7 @@ impl Error for array::TryFromSliceError { #[stable(feature = "rust1", since = "1.0.0")] impl Error for num::ParseFloatError { + #[allow(deprecated)] fn description(&self) -> &str { self.__description() } @@ -537,6 +464,7 @@ impl Error for num::ParseFloatError { #[stable(feature = "rust1", since = "1.0.0")] impl Error for string::FromUtf8Error { + #[allow(deprecated)] fn description(&self) -> &str { "invalid utf-8" } @@ -544,6 +472,7 @@ impl Error for string::FromUtf8Error { #[stable(feature = "rust1", since = "1.0.0")] impl Error for string::FromUtf16Error { + #[allow(deprecated)] fn description(&self) -> &str { "invalid utf-16" } @@ -558,6 +487,7 @@ impl Error for string::ParseError { #[stable(feature = "decode_utf16", since = "1.9.0")] impl Error for char::DecodeUtf16Error { + #[allow(deprecated)] fn description(&self) -> &str { "unpaired surrogate found" } @@ -565,6 +495,7 @@ impl Error for char::DecodeUtf16Error { #[stable(feature = "box_error", since = "1.8.0")] impl<T: Error> Error for Box<T> { + #[allow(deprecated, deprecated_in_future)] fn description(&self) -> &str { Error::description(&**self) } @@ -581,6 +512,7 @@ impl<T: Error> Error for Box<T> { #[stable(feature = "fmt_error", since = "1.11.0")] impl Error for fmt::Error { + #[allow(deprecated)] fn description(&self) -> &str { "an error occurred when formatting an argument" } @@ -588,6 +520,7 @@ impl Error for fmt::Error { #[stable(feature = "try_borrow", since = "1.13.0")] impl Error for cell::BorrowError { + #[allow(deprecated)] fn description(&self) -> &str { "already mutably borrowed" } @@ -595,6 +528,7 @@ impl Error for cell::BorrowError { #[stable(feature = "try_borrow", since = "1.13.0")] impl Error for cell::BorrowMutError { + #[allow(deprecated)] fn description(&self) -> &str { "already borrowed" } @@ -602,6 +536,7 @@ impl Error for cell::BorrowMutError { #[stable(feature = "try_from", since = "1.34.0")] impl Error for char::CharTryFromError { + #[allow(deprecated)] fn description(&self) -> &str { "converted integer out of range for `char`" } @@ -609,6 +544,7 @@ impl Error for char::CharTryFromError { #[stable(feature = "char_from_str", since = "1.20.0")] impl Error for char::ParseCharError { + #[allow(deprecated)] fn description(&self) -> &str { self.__description() } @@ -846,16 +782,8 @@ mod tests { } } - impl Error for A { - fn description(&self) -> &str { - "A-desc" - } - } - impl Error for B { - fn description(&self) -> &str { - "A-desc" - } - } + impl Error for A {} + impl Error for B {} #[test] fn downcasting() { |