limq

Trait Controller

Source 
pub trait Controller {
    type Item;

    // Required methods
    fn is_full(&self, q: &VecDeque<Self::Item>) -> bool;
    fn is_overflow(&self, q: &VecDeque<Self::Item>) -> bool;
    fn check(
        &self,
        q: &VecDeque<Self::Item>,
        item: &Self::Item,
    ) -> Result<(), CheckErr>;
    fn reg(&mut self, q: &VecDeque<Self::Item>, item: &Self::Item);
    fn dereg(&mut self, item: &Self::Item);

    // Provided method
    fn size_hint(&self) -> Option<usize> { ... }
}
Expand description

Implemented for objects that are used to monitor/control queue limits.

Required Associated Types§

Source

type Item

Queue element type.

Required Methods§

Source

fn is_full(&self, q: &VecDeque<Self::Item>) -> bool

Check if queue is full/overflown.

Implementor return true if queue is either full or has overflown.

If an implementation does not impose any upper limits, this must return false.

Source

fn is_overflow(&self, q: &VecDeque<Self::Item>) -> bool

Check if queue is overflown.

Returns true if there’s more data than is maximum allowed. Returns false if the queue is exactly full or has less data.

If an implementation does not impose any upper limits, this must return false.

Source

fn check( &self, q: &VecDeque<Self::Item>, item: &Self::Item, ) -> Result<(), CheckErr>

Check whether a new item would fit in queue.

§Errors

CheckErr::CantFit means the item will never, sans potential Controller reconfiguration, be able to fit in the queue. CheckErr::WontFit means the item will currently not fit, but may be able to do so if the operation is retried later.

Source

fn reg(&mut self, q: &VecDeque<Self::Item>, item: &Self::Item)

Register item as included in queue.

At the point this function is called, the item isn’t actually in the queue, but it is just about it be. The implementation should perform all its internal book keeping assuming it has been added.

Source

fn dereg(&mut self, item: &Self::Item)

Deregister an item.

Provided Methods§

Source

fn size_hint(&self) -> Option<usize>

Return a queue size hint.

This is used by the LimQ factory functions to select a capacity for the internal queue.

If None is returned the factory will not select a specific capacity.

Default implementation returns None.

Implementors§