Struct ParXap 

pub struct ParXap<I, Vo, X1, R = DefaultRunner>
where
    R: ParallelRunner,
    I: ConcurrentIter,
    Vo: TransformableValues<Fallibility = Infallible>,
    X1: Fn(I::Item) -> Vo + Sync,
{ /* private fields */ }

A parallel iterator that xaps inputs.

xap is a generalization of one-to-one map, filter-map and flat-map operations.

Implementations

impl<E, T, R, Vo, X1> ParXap<ConcurrentRecursiveIter<T, E>, Vo, X1, R>

where T: Send + Sync, E: Fn(&T, &Queue<'_, T>) + Sync, R: ParallelRunner + Clone, X1: Fn(T) -> Vo + Sync, Vo: TransformableValues<Fallibility = Infallible>,

pub fn linearize(self) -> ParXap<ConIterVec<T>, Vo, X1, R>

Even with exact length, a recursive parallel iterator is much more dynamic than a flat parallel iterator. This dynamic nature of shrinking and growing concurrently requires a greater parallelization overhead. An alternative approach is to eagerly discover all tasks and then perform the parallel computation over the flattened input of tasks.

The linearize approach works in two parallelization phases:

• first phase to linearize the inputs in parallel over the non-linear data, and
• second phase to perform the computation in parallel over the linear data.

See into_par_rec and into_par_rec_exact for examples.

Trait Implementations

impl<I, Vo, X1, R> ParIter<R> for ParXap<I, Vo, X1, R>

where R: ParallelRunner, I: ConcurrentIter, Vo: TransformableValues<Fallibility = Infallible>, X1: Fn(I::Item) -> Vo + Sync,

type Item = <Vo as Values>::Item

Element type of the parallel iterator.

fn con_iter(&self) -> &impl ConcurrentIter

Returns a reference to the input concurrent iterator.

fn params(&self) -> Params

Parameters of the parallel iterator.

fn num_threads(self, num_threads: impl Into<NumThreads>) -> Self

Sets the number of threads to be used in the parallel execution. Integers can be used as the argument with the following mapping:

fn chunk_size(self, chunk_size: impl Into<ChunkSize>) -> Self

Sets the number of elements to be pulled from the concurrent iterator during the parallel execution. When integers are used as argument, the following mapping applies:

fn iteration_order(self, collect: IterationOrder) -> Self

Sets the iteration order of the parallel computation.

fn with_runner<Q: ParallelRunner>( self, orchestrator: Q, ) -> impl ParIter<Q, Item = Self::Item>

Rather than the DefaultRunner, uses the parallel runner Q which implements ParallelRunner.

fn using<U, F>( self, using: F, ) -> impl ParIterUsing<UsingFun<F, U>, R, Item = <Self as ParIter<R>>::Item>

where U: 'static, F: Fn(usize) -> U + Sync,

Converts the ParIter into ParIterUsing which will have access to a mutable reference of the used variable throughout the computation.

fn using_clone<U>( self, value: U, ) -> impl ParIterUsing<UsingClone<U>, R, Item = <Self as ParIter<R>>::Item>

where U: Clone + 'static,

Converts the ParIter into ParIterUsing which will have access to a mutable reference of the used variable throughout the computation.

fn map<Out, Map>(self, map: Map) -> impl ParIter<R, Item = Out>

where Map: Fn(Self::Item) -> Out + Sync + Clone,

Takes a closure map and creates a parallel iterator which calls that closure on each element.

fn filter<Filter>(self, filter: Filter) -> impl ParIter<R, Item = Self::Item>

where Filter: Fn(&Self::Item) -> bool + Sync + Clone,

Creates an iterator which uses a closure filter to determine if an element should be yielded.

fn flat_map<IOut, FlatMap>( self, flat_map: FlatMap, ) -> impl ParIter<R, Item = IOut::Item>

where IOut: IntoIterator, FlatMap: Fn(Self::Item) -> IOut + Sync + Clone,

Creates an iterator that works like map, but flattens nested structure.

fn filter_map<Out, FilterMap>( self, filter_map: FilterMap, ) -> impl ParIter<R, Item = Out>

where FilterMap: Fn(Self::Item) -> Option<Out> + Sync + Clone,

Creates an iterator that both filters and maps.

fn take_while<While>( self, take_while: While, ) -> impl ParIter<R, Item = Self::Item>

where While: Fn(&Self::Item) -> bool + Sync + Clone,

Creates an iterator that yields elements based on the predicate take_while.

fn into_fallible_result<Out, Err>( self, ) -> impl ParIterResult<R, Item = Out, Err = Err>

where Self::Item: IntoResult<Out, Err>,

Transforms a parallel iterator where elements are of the result type; i.e., ParIter<R, Item = Result<T, E>>, into fallible parallel iterator with item type T and error type E; i.e., into ParIterResult<R, Item = T, Err = E>.

fn collect_into<C>(self, output: C) -> C

where C: ParCollectInto<Self::Item>,

Collects all the items from an iterator into a collection.

fn reduce<Reduce>(self, reduce: Reduce) -> Option<Self::Item>

where Self::Item: Send, Reduce: Fn(Self::Item, Self::Item) -> Self::Item + Sync,

Reduces the elements to a single one, by repeatedly applying a reducing operation.

fn first(self) -> Option<Self::Item>

where Self::Item: Send,

Returns the first (or any) element of the iterator; returns None if it is empty.

fn with_pool<P: ParThreadPool>( self, pool: P, ) -> impl ParIter<RunnerWithPool<P, R::Executor>, Item = Self::Item>

Rather than DefaultPool, uses the parallel runner with the given pool implementing ParThreadPool.

fn into_fallible_option<T>(self) -> impl ParIterOption<R, Item = T>

where Self::Item: IntoOption<T>,

Transforms a parallel iterator where elements are of the option type; i.e., ParIter<R, Item = Option<T>>, into fallible parallel iterator with item type T; i.e., into ParIterOption<R, Item = T>.

fn inspect<Operation>( self, operation: Operation, ) -> impl ParIter<R, Item = Self::Item>

where Operation: Fn(&Self::Item) + Sync + Clone,

Does something with each element of an iterator, passing the value on.

fn map_while<Out, MapWhile>( self, map_while: MapWhile, ) -> impl ParIter<R, Item = Out>

where MapWhile: Fn(Self::Item) -> Option<Out> + Sync + Clone,

Creates an iterator that both yields elements based on the predicate map_while and maps.

fn copied<'a, T>(self) -> impl ParIter<R, Item = T>

where T: 'a + Copy, Self: ParIter<R, Item = &'a T>,

Creates an iterator which copies all of its elements.

fn cloned<'a, T>(self) -> impl ParIter<R, Item = T>

where T: 'a + Clone, Self: ParIter<R, Item = &'a T>,

Creates an iterator which clones all of its elements.

fn flatten(self) -> impl ParIter<R, Item = <Self::Item as IntoIterator>::Item>

where Self::Item: IntoIterator,

Creates an iterator that flattens nested structure.

fn collect<C>(self) -> C

where C: ParCollectInto<Self::Item>,

Transforms an iterator into a collection.

fn all<Predicate>(self, predicate: Predicate) -> bool

where Self::Item: Send, Predicate: Fn(&Self::Item) -> bool + Sync,

Tests if every element of the iterator matches a predicate.

fn any<Predicate>(self, predicate: Predicate) -> bool

where Self::Item: Send, Predicate: Fn(&Self::Item) -> bool + Sync,

Tests if any element of the iterator matches a predicate.

fn count(self) -> usize

Consumes the iterator, counting the number of iterations and returning it.

fn for_each<Operation>(self, operation: Operation)

where Operation: Fn(Self::Item) + Sync,

Calls a closure on each element of an iterator.

fn max(self) -> Option<Self::Item>

where Self::Item: Ord + Send,

Returns the maximum element of an iterator.

fn max_by<Compare>(self, compare: Compare) -> Option<Self::Item>

where Self::Item: Send, Compare: Fn(&Self::Item, &Self::Item) -> Ordering + Sync,

Returns the element that gives the maximum value with respect to the specified compare function.

fn max_by_key<Key, GetKey>(self, key: GetKey) -> Option<Self::Item>

where Self::Item: Send, Key: Ord, GetKey: Fn(&Self::Item) -> Key + Sync,

Returns the element that gives the maximum value from the specified function.

fn min(self) -> Option<Self::Item>

where Self::Item: Ord + Send,

Returns the minimum element of an iterator.

fn min_by<Compare>(self, compare: Compare) -> Option<Self::Item>

where Self::Item: Send, Compare: Fn(&Self::Item, &Self::Item) -> Ordering + Sync,

Returns the element that gives the minimum value with respect to the specified compare function.

fn min_by_key<Key, GetKey>(self, get_key: GetKey) -> Option<Self::Item>

where Self::Item: Send, Key: Ord, GetKey: Fn(&Self::Item) -> Key + Sync,

Returns the element that gives the minimum value from the specified function.

fn sum<Out>(self) -> Out

where Self::Item: Sum<Out>, Out: Send,

Sums the elements of an iterator.

fn find<Predicate>(self, predicate: Predicate) -> Option<Self::Item>

where Self::Item: Send, Predicate: Fn(&Self::Item) -> bool + Sync,

Searches for an element of an iterator that satisfies a predicate.

impl<I, Vo, X1, R> Send for ParXap<I, Vo, X1, R>

where R: ParallelRunner, I: ConcurrentIter, Vo: TransformableValues<Fallibility = Infallible>, X1: Fn(I::Item) -> Vo + Sync,

impl<I, Vo, X1, R> Sync for ParXap<I, Vo, X1, R>

where R: ParallelRunner, I: ConcurrentIter, Vo: TransformableValues<Fallibility = Infallible>, X1: Fn(I::Item) -> Vo + Sync,