Enum style::properties::StyleStructRef

pub enum StyleStructRef<'a, T: 'static> {
    Borrowed(&'a BuilderArc<T>),
    Owned(UniqueArc<T>),
    Vacated,
}

A reference to a style struct of the parent, or our own style struct.

Variants

Borrowed(&'a BuilderArc<T>)

A borrowed struct from the parent, for example, for inheriting style.

Owned(UniqueArc<T>)

An owned struct, that we’ve already mutated.

Vacated

Temporarily vacated, will panic if accessed

Implementations

impl<'a, T> StyleStructRef<'a, T>where
    T: Clone + 'a,

pub fn mutate(&mut self) -> &mut T

Ensure a mutable reference of this value exists, either cloning the borrowed value, or returning the owned one.

pub fn ptr_eq(&self, struct_to_copy_from: &T) -> bool

Whether this is pointer-equal to the struct we’re going to copy the value from.

This is used to avoid allocations when people write stuff like font: inherit or such all: initial.

pub fn take(&mut self) -> UniqueArc<T>

Extract a unique Arc from this struct, vacating it.

The vacated state is a transient one, please put the Arc back when done via put(). This function is to be used to separate the struct being mutated from the computed context

pub fn put(&mut self, arc: UniqueArc<T>)

Replace vacated ref with an arc

pub fn get_if_mutated(&mut self) -> Option<&mut T>

Get a mutable reference to the owned struct, or None if the struct hasn’t been mutated.

pub fn build(self) -> Arc<T>

Returns an Arc to the internal struct, constructing one if appropriate.

Trait Implementations

impl<'a, T: 'a> Deref for StyleStructRef<'a, T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.