Struct arrayvec::ArrayString

pub struct ArrayString<A: Array<Item = u8>> { /* fields omitted */ }

A string with a fixed capacity.

The ArrayString is a string backed by a fixed size array. It keeps track of its length.

The string is a contiguous value that you can store directly on the stack if needed.

Methods

impl<A: Array<Item = u8>> ArrayString<A>

pub fn new() -> ArrayString<A>

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);

pub 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);

pub fn from_byte_string(b: &A) -> 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();

pub fn capacity(&self) -> usize

Return the capacity of the ArrayString.

use arrayvec::ArrayString;

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

pub 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());

pub 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");

pub 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');

pub 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");

pub 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");

pub 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);

pub 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");

pub 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');

pub fn clear(&mut self)

Make the string empty.

pub 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.

pub fn as_str(&self) -> &str

Return a string slice of the whole ArrayString.

Trait Implementations

impl<A: Array<Item = u8>> DerefMut for ArrayString<A>

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

Mutably dereferences the value.

impl<A: Array<Item = u8>> PartialEq<ArrayString<A>> for ArrayString<A>

fn eq(&self, rhs: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<A: Array<Item = u8>> PartialEq<str> for ArrayString<A>

fn eq(&self, rhs: &str) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<A: Array<Item = u8>> PartialEq<ArrayString<A>> for str

fn eq(&self, rhs: &ArrayString<A>) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<A: Array<Item = u8>> Eq for ArrayString<A>

impl<A: Array<Item = u8>> Ord for ArrayString<A>

fn cmp(&self, rhs: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

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

Restrict a value to a certain interval.

impl<A: Array<Item = u8>> PartialOrd<ArrayString<A>> for ArrayString<A>

fn partial_cmp(&self, rhs: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, rhs: &Self) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, rhs: &Self) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, rhs: &Self) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, rhs: &Self) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<A: Array<Item = u8>> PartialOrd<str> for ArrayString<A>

fn partial_cmp(&self, rhs: &str) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, rhs: &str) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, rhs: &str) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, rhs: &str) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, rhs: &str) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<A: Array<Item = u8>> PartialOrd<ArrayString<A>> for str

fn partial_cmp(&self, rhs: &ArrayString<A>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, rhs: &ArrayString<A>) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, rhs: &ArrayString<A>) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, rhs: &ArrayString<A>) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, rhs: &ArrayString<A>) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<A: Array<Item = u8>> Hash for ArrayString<A>

fn hash<H: Hasher>(&self, h: &mut H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<A: Array<Item = u8>> Deref for ArrayString<A>

type Target = str

The resulting type after dereferencing.

fn deref(&self) -> &str

Dereferences the value.

impl<A: Array<Item = u8>> Debug for ArrayString<A>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<A: Array<Item = u8>> Display for ArrayString<A>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<A: Array<Item = u8>> Write for ArrayString<A>

Write appends written data to the end of the string.

fn write_char(&mut self, c: char) -> Result

Writes a [char] into this writer, returning whether the write succeeded.

fn write_str(&mut self, s: &str) -> Result

Writes a slice of bytes into this writer, returning whether the write succeeded.

fn write_fmt(&mut self, args: Arguments) -> Result<(), Error>

Glue for usage of the [write!] macro with implementors of this trait.

impl<A: Array<Item = u8>> AsRef<str> for ArrayString<A>

fn as_ref(&self) -> &str

Performs the conversion.

impl<A: Copy + Array<Item = u8>> Copy for ArrayString<A> where
    A::Index: Copy, 

impl<A: Array<Item = u8> + Copy> Clone for ArrayString<A>

fn clone(&self) -> ArrayString<A>

Returns a copy of the value.

fn clone_from(&mut self, rhs: &Self)

Performs copy-assignment from source.

impl<A: Array<Item = u8>> Default for ArrayString<A>

fn default() -> ArrayString<A>

Return an empty ArrayString

impl<A: Array<Item = u8>> Borrow<str> for ArrayString<A>

fn borrow(&self) -> &str

Immutably borrows from an owned value.