std:🧵:FromUtf8Error - Rust (original) (raw)
Struct std::string::FromUtf8Error1.0.0 [−] [src]
pub struct FromUtf8Error { /* fields omitted */ }
A possible error value when converting a String from a UTF-8 byte vector.
This type is the error type for the from_utf8 method on String. It is designed in such a way to carefully avoid reallocations: theinto_bytes method will give back the byte vector that was used in the conversion attempt.
The Utf8Error type provided by std::str represents an error that may occur when converting a slice of u8s to a &str. In this sense, it's an analogue to FromUtf8Error, and you can get one from a FromUtf8Errorthrough the utf8_error method.
Basic usage:
let bytes = vec![0, 159];
let value = String::from_utf8(bytes);
assert!(value.is_err()); assert_eq!(vec![0, 159], value.unwrap_err().into_bytes());Run
impl [FromUtf8Error](../../std/string/struct.FromUtf8Error.html "struct std:🧵:FromUtf8Error")[src]
pub fn [as_bytes](#method.as%5Fbytes)(&self) -> [&[](../primitive.slice.html)[u8](../primitive.u8.html)[]](../primitive.slice.html)[src]
🔬 This is a nightly-only experimental API. (from_utf8_error_as_bytes #40895)
recently added
Returns a slice of [u8]s bytes that were attempted to convert to a String.
Basic usage:
#![feature(from_utf8_error_as_bytes)]
let bytes = vec![0, 159];
let value = String::from_utf8(bytes);
assert_eq!(&[0, 159], value.unwrap_err().as_bytes());Run
pub fn [into_bytes](#method.into%5Fbytes)(self) -> [Vec](../../std/vec/struct.Vec.html "struct std::vec::Vec")<[u8](../primitive.u8.html)>[src]
Returns the bytes that were attempted to convert to a String.
This method is carefully constructed to avoid allocation. It will consume the error, moving out the bytes, so that a copy of the bytes does not need to be made.
Basic usage:
let bytes = vec![0, 159];
let value = String::from_utf8(bytes);
assert_eq!(vec![0, 159], value.unwrap_err().into_bytes());Run
pub fn [utf8_error](#method.utf8%5Ferror)(&self) -> [Utf8Error](../../std/str/struct.Utf8Error.html "struct std::str::Utf8Error")[src]
Fetch a Utf8Error to get more details about the conversion failure.
The Utf8Error type provided by std::str represents an error that may occur when converting a slice of u8s to a &str. In this sense, it's an analogue to FromUtf8Error. See its documentation for more details on using it.
Basic usage:
let bytes = vec![0, 159];
let error = String::from_utf8(bytes).unwrap_err().utf8_error();
assert_eq!(1, error.valid_up_to());Run