Struct spirit::fragment::driver::CacheSimilar

pub struct CacheSimilar<F: Fragment + ToOwned> { /* fields omitted */ }

A Driver that caches both created Resources and their Seeds to create as little as possible.

It uses the Comparable trait to decide if it needs to create the Resource complete from scratch, if it can reuse the old Seed or if it can even keep the old instance. This is a good driver for cases where the Seed is some kind of unique resource and changing the resource by creating a completely new instance while the old one existed wouldn’t work. An example of this is the bound ports on listening sockets ‒ while we might want to attach different configuration to the same socket, opening a new socket with the same port would not work. Therefore, the socket is somewhere within the Seed and it is reused if the port doesn’t change.

Trait Implementations

impl<F: Debug + Fragment + ToOwned> Debug for CacheSimilar<F> where
    F::Owned: Debug,
    F::Seed: Debug, 

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

Formats the value using the given formatter.

impl<F: Fragment + ToOwned> Default for CacheSimilar<F>

fn default() -> Self

Returns the “default value” for a type.

impl<F> Driver<F> for CacheSimilar<F> where
    F: Debug + Fragment + ToOwned + Comparable<<F as ToOwned>::Owned>, 

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<F::Resource, I, F>, 

Issues the instructions how to transition to the new fragment.

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 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 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.