Struct FromUtf8Error

pub struct FromUtf8Error<A = Global>
where
    A: Allocator,
{ /* private fields */ }

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

use rune::alloc::{try_vec, String};

// some invalid bytes, in a vector
let bytes = try_vec![0, 159];

let value = String::from_utf8(bytes);

assert!(value.is_err());
assert_eq!(try_vec![0, 159], value.unwrap_err().into_bytes());

Implementations

impl<A> FromUtf8Error<A>

where A: Allocator,

pub fn as_bytes(&self) -> &[u8]

Returns a slice of u8s bytes that were attempted to convert to a String.

Examples

use rune::alloc::{try_vec, String};

// some invalid bytes, in a vector
let bytes = try_vec![0, 159];

let value = String::from_utf8(bytes);

assert_eq!(&[0, 159], value.unwrap_err().as_bytes());

pub fn into_bytes(self) -> Vec<u8, A>

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

use rune::alloc::{try_vec, String};

// some invalid bytes, in a vector
let bytes = try_vec![0, 159];

let value = String::from_utf8(bytes);

assert_eq!(try_vec![0, 159], value.unwrap_err().into_bytes());

pub 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 u8s to a &str. In this sense, it’s an analogue to FromUtf8Error. See its documentation for more details on using it.

Examples

use rune::alloc::{try_vec, String};

// some invalid bytes, in a vector
let bytes = try_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());

Trait Implementations

impl Any for FromUtf8Error

Available on crate feature alloc only.

const ANY_TYPE_INFO: AnyTypeInfo = _

The compile-time type information know for the type.

impl<A> Debug for FromUtf8Error<A>

where A: Allocator,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<A> Display for FromUtf8Error<A>

where A: Allocator,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<A> Error for FromUtf8Error<A>

where A: Allocator,

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl InstallWith for FromUtf8Error

Available on crate feature alloc only.

fn install_with(module: &mut Module) -> Result<(), ContextError>

Hook to install more things into the module.

impl MaybeTypeOf for FromUtf8Error

Available on crate feature alloc only.

fn maybe_type_of() -> Result<DocType>

Type information for the given type.

impl Named for FromUtf8Error

Available on crate feature alloc only.

const ITEM: &'static Item = _

The name item.

fn full_name(f: &mut Formatter<'_>) -> Result

The exact type name

fn display() -> impl Display

Return a display wrapper for the named type.

impl<A> PartialEq for FromUtf8Error<A>

where A: Allocator,

fn eq(&self, other: &FromUtf8Error<A>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl TypeHash for FromUtf8Error

Available on crate feature alloc only.

const HASH: Hash = _

The complete type hash of the type including type parameters which uniquely identifiers a given type.

impl TypeOf for FromUtf8Error

Available on crate feature alloc only.

const PARAMETERS: Hash = _

Type parameters for the type.

const STATIC_TYPE_INFO: AnyTypeInfo = <Self as crate::Any>::ANY_TYPE_INFO

Access diagnostical type information for the current type.

fn type_info() -> TypeInfo

Get type info associated with the current type.

impl UnsafeToMut for FromUtf8Error

Available on crate feature alloc only.

type Guard = RawValueGuard

The raw guard returned.

unsafe fn unsafe_to_mut<'a>( value: Value, ) -> Result<(&'a mut Self, Self::Guard), RuntimeError>

Safety

impl UnsafeToRef for FromUtf8Error

Available on crate feature alloc only.

type Guard = RawValueGuard

The raw guard returned.

unsafe fn unsafe_to_ref<'a>( value: Value, ) -> Result<(&'a Self, Self::Guard), RuntimeError>

Safety

impl UnsafeToValue for &FromUtf8Error

Available on crate feature alloc only.

type Guard = ValueRefGuard

The type used to guard the unsafe value conversion.

unsafe fn unsafe_to_value(self) -> Result<(Value, Self::Guard), RuntimeError>

Convert into a value.

impl UnsafeToValue for &mut FromUtf8Error

Available on crate feature alloc only.

type Guard = ValueMutGuard

The type used to guard the unsafe value conversion.

unsafe fn unsafe_to_value(self) -> Result<(Value, Self::Guard), RuntimeError>

Convert into a value.

impl<A> Eq for FromUtf8Error<A>

where A: Allocator,