Struct ArrayString

impl<const CAP: usize> ArrayString<CAP>

fn new() -> ArrayString<CAP>

Create a new empty ArrayString.

Capacity is inferred from the type parameter.

use arrayvec::ArrayString;

let mut string = ArrayString::<16>::new();
string.push_str("foo");
assert_eq!(&string[..], "foo");
assert_eq!(string.capacity(), 16);

const fn new_const() -> ArrayString<CAP>

Create a new empty ArrayString (const fn).

Capacity is inferred from the type parameter.

use arrayvec::ArrayString;

static ARRAY: ArrayString<1024> = ArrayString::new_const();

const fn len(&self) -> usize

Return the length of the string.

const fn is_empty(&self) -> bool

Returns whether the string is empty.

fn from(s: &str) -> Result<Self, CapacityError<&str>>

Create a new ArrayString from a str.

Capacity is inferred from the type parameter.

Errors if the backing array is not large enough to fit the string.

use arrayvec::ArrayString;

let mut string = ArrayString::<3>::from("foo").unwrap();
assert_eq!(&string[..], "foo");
assert_eq!(string.len(), 3);
assert_eq!(string.capacity(), 3);

fn from_byte_string(b: &[u8; CAP]) -> Result<Self, Utf8Error>

Create a new ArrayString from a byte string literal.

Errors if the byte string literal is not valid UTF-8.

use arrayvec::ArrayString;

let string = ArrayString::from_byte_string(b"hello world").unwrap();

fn zero_filled() -> Self

Create a new ArrayString value fully filled with ASCII NULL characters (\0). Useful to be used as a buffer to collect external data or as a buffer for intermediate processing.

use arrayvec::ArrayString;

let string = ArrayString::<16>::zero_filled();
assert_eq!(string.len(), 16);

const fn capacity(&self) -> usize

Return the capacity of the ArrayString.

use arrayvec::ArrayString;

let string = ArrayString::<3>::new();
assert_eq!(string.capacity(), 3);

const fn is_full(&self) -> bool

Return if the ArrayString is completely filled.

use arrayvec::ArrayString;

let mut string = ArrayString::<1>::new();
assert!(!string.is_full());
string.push_str("A");
assert!(string.is_full());

const fn remaining_capacity(&self) -> usize

Returns the capacity left in the ArrayString.

use arrayvec::ArrayString;

let mut string = ArrayString::<3>::from("abc").unwrap();
string.pop();
assert_eq!(string.remaining_capacity(), 1);

fn push(&mut self, c: char)

Adds the given char to the end of the string.

Panics if the backing array is not large enough to fit the additional char.

use arrayvec::ArrayString;

let mut string = ArrayString::<2>::new();

string.push('a');
string.push('b');

assert_eq!(&string[..], "ab");

fn try_push(&mut self, c: char) -> Result<(), CapacityError<char>>

Adds the given char to the end of the string.

Returns Ok if the push succeeds.

Errors if the backing array is not large enough to fit the additional char.

use arrayvec::ArrayString;

let mut string = ArrayString::<2>::new();

string.try_push('a').unwrap();
string.try_push('b').unwrap();
let overflow = string.try_push('c');

assert_eq!(&string[..], "ab");
assert_eq!(overflow.unwrap_err().element(), 'c');

fn push_str(&mut self, s: &str)

Adds the given string slice to the end of the string.

Panics if the backing array is not large enough to fit the string.

use arrayvec::ArrayString;

let mut string = ArrayString::<2>::new();

string.push_str("a");
string.push_str("d");

assert_eq!(&string[..], "ad");

fn try_push_str<'a>(&mut self, s: &'a str) -> Result<(), CapacityError<&'a str>>

Adds the given string slice to the end of the string.

Returns Ok if the push succeeds.

Errors if the backing array is not large enough to fit the string.

use arrayvec::ArrayString;

let mut string = ArrayString::<2>::new();

string.try_push_str("a").unwrap();
let overflow1 = string.try_push_str("bc");
string.try_push_str("d").unwrap();
let overflow2 = string.try_push_str("ef");

assert_eq!(&string[..], "ad");
assert_eq!(overflow1.unwrap_err().element(), "bc");
assert_eq!(overflow2.unwrap_err().element(), "ef");

fn pop(&mut self) -> Option<char>

Removes the last character from the string and returns it.

Returns None if this ArrayString is empty.

use arrayvec::ArrayString;
 
let mut s = ArrayString::<3>::from("foo").unwrap();

assert_eq!(s.pop(), Some('o'));
assert_eq!(s.pop(), Some('o'));
assert_eq!(s.pop(), Some('f'));

assert_eq!(s.pop(), None);

fn truncate(&mut self, new_len: usize)

Shortens this ArrayString to the specified length.

If new_len is greater than the string’s current length, this has no effect.

Panics if new_len does not lie on a char boundary.

use arrayvec::ArrayString;

let mut string = ArrayString::<6>::from("foobar").unwrap();
string.truncate(3);
assert_eq!(&string[..], "foo");
string.truncate(4);
assert_eq!(&string[..], "foo");

fn remove(&mut self, idx: usize) -> char

Removes a char from this ArrayString at a byte position and returns it.

This is an O(n) operation, as it requires copying every element in the array.

Panics if idx is larger than or equal to the ArrayString’s length, or if it does not lie on a char boundary.

use arrayvec::ArrayString;
 
let mut s = ArrayString::<3>::from("foo").unwrap();

assert_eq!(s.remove(0), 'f');
assert_eq!(s.remove(1), 'o');
assert_eq!(s.remove(0), 'o');

fn clear(&mut self)

Make the string empty.

unsafe fn set_len(&mut self, length: usize)

Set the strings’s length.

This function is unsafe because it changes the notion of the number of “valid” bytes in the string. Use with care.

This method uses debug assertions to check the validity of length and may use other debug assertions.

fn as_str(&self) -> &str

Return a string slice of the whole ArrayString.

fn as_mut_str(&mut self) -> &mut str

Return a mutable string slice of the whole ArrayString.

fn as_ptr(&self) -> *const u8

Return a raw pointer to the string's buffer.

fn as_mut_ptr(&mut self) -> *mut u8

Return a raw mutable pointer to the string's buffer.