Struct smol_str::SmolStr

pub struct SmolStr(_);

A SmolStr is a string type that has the following properties:

• size_of::<SmolStr>() == size_of::<String>()
• Clone is O(1)
• Strings are stack-allocated if they are:
  • Up to 22 bytes long
  • Longer than 22 bytes, but substrings of WS (see below). Such strings consist solely of consecutive newlines, followed by consecutive spaces
• If a string does not satisfy the aforementioned conditions, it is heap-allocated

Unlike String, however, SmolStr is immutable. The primary use case for SmolStr is a good enough default storage for tokens of typical programming languages. Strings consisting of a series of newlines, followed by a series of whitespace are a typical pattern in computer programs because of indentation. Note that a specialized interner might be a better solution for some use cases.

Methods

impl SmolStr

pub fn new<T>(text: T) -> SmolStr where
    T: Into<String> + AsRef<str>, 

pub fn as_str(&self) -> &str

pub fn to_string(&self) -> String

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn is_heap_allocated(&self) -> bool

Trait Implementations

impl<T> From<T> for SmolStr where
    T: Into<String> + AsRef<str>, 

fn from(text: T) -> Self

Performs the conversion.

impl From<SmolStr> for String

fn from(text: SmolStr) -> Self

Performs the conversion.

impl Eq for SmolStr

impl Default for SmolStr

fn default() -> SmolStr

Returns the "default value" for a type.

impl PartialEq<SmolStr> for SmolStr

fn eq(&self, other: &SmolStr) -> 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 PartialEq<str> for SmolStr

fn eq(&self, other: &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 PartialEq<SmolStr> for str

fn eq(&self, other: &SmolStr) -> 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> PartialEq<&'a str> for SmolStr

fn eq(&self, other: &&'a 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> PartialEq<SmolStr> for &'a str

fn eq(&self, other: &SmolStr) -> 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 PartialEq<String> for SmolStr

fn eq(&self, other: &String) -> 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 PartialEq<SmolStr> for String

fn eq(&self, other: &SmolStr) -> 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> PartialEq<&'a String> for SmolStr

fn eq(&self, other: &&'a String) -> 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> PartialEq<SmolStr> for &'a String

fn eq(&self, other: &SmolStr) -> 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 Clone for SmolStr

fn clone(&self) -> SmolStr

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for SmolStr

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

Formats the value using the given formatter.

impl Hash for SmolStr

fn hash<H: Hasher>(&self, hasher: &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 Deref for SmolStr

type Target = str

The resulting type after dereferencing.

fn deref(&self) -> &str

Dereferences the value.

impl Display for SmolStr

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

Formats the value using the given formatter.

impl Borrow<str> for SmolStr

fn borrow(&self) -> &str

Immutably borrows from an owned value.