# Struct std::str::Utf8Error [−] [src]

    pub struct Utf8Error {
        // some fields omitted
    }

Errors which can occur when attempting to interpret a sequence of `u8` as a string.

As such, the `from_utf8` family of functions and methods for both `String`s and `&str`s make use of this error, for example.

## Methods

### `impl Utf8Error`

#### `fn valid_up_to(&self) -> usize`

Returns the index in the given string up to which valid UTF-8 was verified.

It is the maximum index such that `from_utf8(input[..index])` would return `Some(_)`.

# Examples

Basic usage:

fn main() { use std::str; // some invalid bytes, in a vector let sparkle_heart = vec![0, 159, 146, 150]; // std::str::from_utf8 returns a Utf8Error let error = str::from_utf8(&sparkle_heart).unwrap_err(); // the first byte is invalid here assert_eq!(1, error.valid_up_to()); }

    use std::str;

    // some invalid bytes, in a vector
    let sparkle_heart = vec![0, 159, 146, 150];

    // std::str::from_utf8 returns a Utf8Error
    let error = str::from_utf8(&sparkle_heart).unwrap_err();

    // the first byte is invalid here
    assert_eq!(1, error.valid_up_to());

## Trait Implementations

### `impl Display for Utf8Error`

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

### `impl Error for Utf8Error`

#### `fn description(&self) -> &str`

#### `fn cause(&self) -> Option<&Error>`

### Derived Implementations

### `impl Debug for Utf8Error`

#### `fn fmt(&self, __arg_0: &mut Formatter) -> Result<(), Error>`

### `impl Clone for Utf8Error`

#### `fn clone(&self) -> Utf8Error`

#### `fn clone_from(&mut self, source: &Self)`

### `impl PartialEq<Utf8Error> for Utf8Error`

#### `fn eq(&self, __arg_0: &Utf8Error) -> bool`

#### `fn ne(&self, __arg_0: &Utf8Error) -> bool`

### `impl Eq for Utf8Error`

### `impl Copy for Utf8Error`

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