# Module std::string 1.0.0 [−] [src]

A UTF-8 encoded, growable string.

This module contains the `String` type, a trait for converting `ToString`s, and several error types that may result from working with `String`s.

# Examples

There are multiple ways to create a new `String` from a string literal:

fn main() { let s = "Hello".to_string(); let s = String::from("world"); let s: String = "also this".into(); }

    let s = "Hello".to_string();

    let s = String::from("world");
    let s: String = "also this".into();

You can create a new `String` from an existing one by concatenating with `+`:

fn main() { let s = "Hello".to_string(); let message = s + " world!"; }

    let s = "Hello".to_string();

    let message = s + " world!";

If you have a vector of valid UTF-8 bytes, you can make a `String` out of it. You can do the reverse too.

fn main() { let sparkle_heart = vec![240, 159, 146, 150]; // We know these bytes are valid, so we'll use `unwrap()`. let sparkle_heart = String::from_utf8(sparkle_heart).unwrap(); assert_eq!("💖", sparkle_heart); let bytes = sparkle_heart.into_bytes(); assert_eq!(bytes, [240, 159, 146, 150]); }

    let sparkle_heart = vec![240, 159, 146, 150];

    // We know these bytes are valid, so we'll use `unwrap()`.
    let sparkle_heart = String::from_utf8(sparkle_heart).unwrap();

    assert_eq!("💖", sparkle_heart);

    let bytes = sparkle_heart.into_bytes();

    assert_eq!(bytes, [240, 159, 146, 150]);

## Structs

Drain | A draining iterator for `String`.
FromUtf16Error | A possible error value when converting a `String` from a UTF-16 byte slice.
FromUtf8Error | A possible error value when converting a `String` from a UTF-8 byte vector.
String | A UTF-8 encoded, growable string.

## Enums

ParseError | An error when parsing a `String`.

## Traits

ToString | A trait for converting a value to a `String`.

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