Struct harfbuzz_rs::Owned

pub struct Owned<T: HarfbuzzObject> { /* fields omitted */ }

A smart pointer that wraps a singly owned harfbuzz object.

A Owned is used to wrap freshly created owned HarfBuzz objects. It permits mutable, non-shared access to the enclosed HarfBuzz value so it can be used e.g. to set up a Font or Face after its creation.

There is no safe way to construct an Owned pointer and usually you don't need to create a Owned yourself, but get it from another function in this crate. You can just use the methods of the wrapped object through its Deref implementation.

Interaction with Shared

When you are finished mutating the inner value, you usually want to pass it to other HarfBuzz functions that expect shared access. Thus you need to convert the Owned to a Shared pointer using .into(). Note however that once a value is converted to a Shared<T>, it will not possible to mutate it anymore.

Methods

impl<T: HarfbuzzObject> Owned<T>

pub unsafe fn from_raw(raw: *mut T::Raw) -> Self

Creates a Owned safely wrapping a raw harfbuzz pointer.

This fully transfers ownership. Use of the original pointer is now forbidden! Unsafe because a dereference of a raw pointer is necessary.

Use this only to wrap freshly created HarfBuzz object that is not shared!

pub fn into_raw(owned: Owned<T>) -> *mut T::Raw

Converts self into the underlying harfbuzz object pointer value. The resulting pointer has to be manually destroyed using hb_TYPE_destroy or be converted back into the wrapper using the from_raw function to avoid leaking memory.

pub fn to_shared(self) -> Shared<T>

Demotes an Owned pointer to a Shared pointer.

Use this method when you don't need exclusive (mutable) access to the object anymore. For differences between Owned and Shared pointers see the documentation on the respective structs.

Note that Shared<T> also implements From<Owned<T>> which allows implicit conversions in many functions.

Trait Implementations

impl<T: Eq + HarfbuzzObject> Eq for Owned<T>

impl<T: HarfbuzzObject> Drop for Owned<T>

fn drop(&mut self)

Executes the destructor for this type.

impl<T: PartialEq + HarfbuzzObject> PartialEq<Owned<T>> for Owned<T>

fn eq(&self, other: &Owned<T>) -> bool

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

fn ne(&self, other: &Owned<T>) -> bool

This method tests for !=.

impl<'a> Default for Owned<Font<'a>>

fn default() -> Self

Returns the "default value" for a type.

impl<T: HarfbuzzObject> From<Owned<T>> for Shared<T>

fn from(t: Owned<T>) -> Self

Performs the conversion.

impl<T: HarfbuzzObject> DerefMut for Owned<T>

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

Mutably dereferences the value.

impl<T: HarfbuzzObject> Deref for Owned<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<T: Debug + HarfbuzzObject> Debug for Owned<T>

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

Formats the value using the given formatter.