Struct std::string::FromUtf8Error
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[src]
pub struct FromUtf8Error {
// some 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: the
into_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 FromUtf8Error
through the utf8_error() method.
Examples
Basic usage:
fn main() { // some invalid bytes, in a vector 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()); }// some invalid bytes, in a vector 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());
Methods
impl FromUtf8Error
fn into_bytes(self) -> Vec<u8>
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.
Examples
Basic usage:
fn main() { // some invalid bytes, in a vector let bytes = vec![0, 159]; let value = String::from_utf8(bytes); assert_eq!(vec![0, 159], value.unwrap_err().into_bytes()); }// some invalid bytes, in a vector let bytes = vec![0, 159]; let value = String::from_utf8(bytes); assert_eq!(vec![0, 159], value.unwrap_err().into_bytes());
fn utf8_error(&self) -> Utf8Error
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 [u8]s to a [&str]. In this sense, it's
an analogue to FromUtf8Error. See its documentation for more details
on using it.
Examples
Basic usage:
fn main() { // some invalid bytes, in a vector let bytes = vec![0, 159]; let error = String::from_utf8(bytes).unwrap_err().utf8_error(); // the first byte is invalid here assert_eq!(1, error.valid_up_to()); }// some invalid bytes, in a vector let bytes = vec![0, 159]; let error = String::from_utf8(bytes).unwrap_err().utf8_error(); // the first byte is invalid here assert_eq!(1, error.valid_up_to());