Struct spirit::fragment::driver::OnceDriver

pub struct OnceDriver<F: ToOwned> { /* fields omitted */ }

A Driver for a single-shot initialization.

This driver creates the resource only the first time it is called. On an attempt to call it again it warns if the value of the fragment is different.

Trait Implementations

impl<F> Default for OnceDriver<F> where
    F: ToOwned, 

fn default() -> Self

Returns the "default value" for a type.

impl<F> Driver<F> for OnceDriver<F> where
    F: Fragment + PartialEq<<F as ToOwned>::Owned> + ToOwned + 'static, 

type SubFragment = F

The smaller Fragment the driver cuts F into.

fn instructions<T, I>(
    &mut self,
    fragment: &F,
    transform: &mut T,
    name: &'static str
) -> Result<Vec<Instruction<T::OutputResource>>, Vec<AnyError>> where
    T: Transformation<<Self::SubFragment as Fragment>::Resource, I, Self::SubFragment>, 

Issues the instructions how to transition to the new fragment.

fn confirm(&mut self, _name: &'static str)

Call to this method informs the Driver that the instructions returned by the last call to instructions were followed and the changes have taken place.

fn abort(&mut self, _name: &'static str)

Call to this method informs the Driver that the instructions returned by the last call to instructions were not followed and were dropped.

fn maybe_cached(&self, fragment: &F, _name: &'static str) -> bool

Informs if there's a chance the new fragment will use something in the Driver's cache if applied.