# 1.20.0[−][src]Function std::str::from_utf8_mut

    pub fn from_utf8_mut(v: &mut [u8]) -> Result<&mut str, Utf8Error>

Converts a mutable slice of bytes to a mutable string slice.

# Examples

Basic usage:

    use std::str;

    // "Hello, Rust!" as a mutable vector
    let mut hellorust = vec![72, 101, 108, 108, 111, 44, 32, 82, 117, 115, 116, 33];

    // As we know these bytes are valid, we can use `unwrap()`
    let outstr = str::from_utf8_mut(&mut hellorust).unwrap();

    assert_eq!("Hello, Rust!", outstr);Run

Incorrect bytes:

    use std::str;

    // Some invalid bytes in a mutable vector
    let mut invalid = vec![128, 223];

    assert!(str::from_utf8_mut(&mut invalid).is_err());Run

See the docs for `Utf8Error` for more details on the kinds of errors that can be returned.

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