| use super::plumbing::*; |
| use super::*; |
| |
| use super::private::Try; |
| use std::fmt::{self, Debug}; |
| use std::marker::PhantomData; |
| |
| impl<U, I, ID, F> TryFold<I, U, ID, F> |
| where |
| I: ParallelIterator, |
| F: Fn(U::Ok, I::Item) -> U + Sync + Send, |
| ID: Fn() -> U::Ok + Sync + Send, |
| U: Try + Send, |
| { |
| pub(super) fn new(base: I, identity: ID, fold_op: F) -> Self { |
| TryFold { |
| base, |
| identity, |
| fold_op, |
| marker: PhantomData, |
| } |
| } |
| } |
| |
| /// `TryFold` is an iterator that applies a function over an iterator producing a single value. |
| /// This struct is created by the [`try_fold()`] method on [`ParallelIterator`] |
| /// |
| /// [`try_fold()`]: trait.ParallelIterator.html#method.try_fold |
| /// [`ParallelIterator`]: trait.ParallelIterator.html |
| #[must_use = "iterator adaptors are lazy and do nothing unless consumed"] |
| #[derive(Clone)] |
| pub struct TryFold<I, U, ID, F> { |
| base: I, |
| identity: ID, |
| fold_op: F, |
| marker: PhantomData<U>, |
| } |
| |
| impl<U, I: ParallelIterator + Debug, ID, F> Debug for TryFold<I, U, ID, F> { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| f.debug_struct("TryFold").field("base", &self.base).finish() |
| } |
| } |
| |
| impl<U, I, ID, F> ParallelIterator for TryFold<I, U, ID, F> |
| where |
| I: ParallelIterator, |
| F: Fn(U::Ok, I::Item) -> U + Sync + Send, |
| ID: Fn() -> U::Ok + Sync + Send, |
| U: Try + Send, |
| { |
| type Item = U; |
| |
| fn drive_unindexed<C>(self, consumer: C) -> C::Result |
| where |
| C: UnindexedConsumer<Self::Item>, |
| { |
| let consumer1 = TryFoldConsumer { |
| base: consumer, |
| identity: &self.identity, |
| fold_op: &self.fold_op, |
| marker: PhantomData, |
| }; |
| self.base.drive_unindexed(consumer1) |
| } |
| } |
| |
| struct TryFoldConsumer<'c, U, C, ID, F> { |
| base: C, |
| identity: &'c ID, |
| fold_op: &'c F, |
| marker: PhantomData<U>, |
| } |
| |
| impl<'r, U, T, C, ID, F> Consumer<T> for TryFoldConsumer<'r, U, C, ID, F> |
| where |
| C: Consumer<U>, |
| F: Fn(U::Ok, T) -> U + Sync, |
| ID: Fn() -> U::Ok + Sync, |
| U: Try + Send, |
| { |
| type Folder = TryFoldFolder<'r, C::Folder, U, F>; |
| type Reducer = C::Reducer; |
| type Result = C::Result; |
| |
| fn split_at(self, index: usize) -> (Self, Self, Self::Reducer) { |
| let (left, right, reducer) = self.base.split_at(index); |
| ( |
| TryFoldConsumer { base: left, ..self }, |
| TryFoldConsumer { |
| base: right, |
| ..self |
| }, |
| reducer, |
| ) |
| } |
| |
| fn into_folder(self) -> Self::Folder { |
| TryFoldFolder { |
| base: self.base.into_folder(), |
| result: Ok((self.identity)()), |
| fold_op: self.fold_op, |
| } |
| } |
| |
| fn full(&self) -> bool { |
| self.base.full() |
| } |
| } |
| |
| impl<'r, U, T, C, ID, F> UnindexedConsumer<T> for TryFoldConsumer<'r, U, C, ID, F> |
| where |
| C: UnindexedConsumer<U>, |
| F: Fn(U::Ok, T) -> U + Sync, |
| ID: Fn() -> U::Ok + Sync, |
| U: Try + Send, |
| { |
| fn split_off_left(&self) -> Self { |
| TryFoldConsumer { |
| base: self.base.split_off_left(), |
| ..*self |
| } |
| } |
| |
| fn to_reducer(&self) -> Self::Reducer { |
| self.base.to_reducer() |
| } |
| } |
| |
| struct TryFoldFolder<'r, C, U: Try, F> { |
| base: C, |
| fold_op: &'r F, |
| result: Result<U::Ok, U::Error>, |
| } |
| |
| impl<'r, C, U, F, T> Folder<T> for TryFoldFolder<'r, C, U, F> |
| where |
| C: Folder<U>, |
| F: Fn(U::Ok, T) -> U + Sync, |
| U: Try, |
| { |
| type Result = C::Result; |
| |
| fn consume(mut self, item: T) -> Self { |
| let fold_op = self.fold_op; |
| if let Ok(acc) = self.result { |
| self.result = fold_op(acc, item).into_result(); |
| } |
| self |
| } |
| |
| fn complete(self) -> C::Result { |
| let item = match self.result { |
| Ok(ok) => U::from_ok(ok), |
| Err(error) => U::from_error(error), |
| }; |
| self.base.consume(item).complete() |
| } |
| |
| fn full(&self) -> bool { |
| self.result.is_err() || self.base.full() |
| } |
| } |
| |
| // /////////////////////////////////////////////////////////////////////////// |
| |
| impl<U, I, F> TryFoldWith<I, U, F> |
| where |
| I: ParallelIterator, |
| F: Fn(U::Ok, I::Item) -> U + Sync, |
| U: Try + Send, |
| U::Ok: Clone + Send, |
| { |
| pub(super) fn new(base: I, item: U::Ok, fold_op: F) -> Self { |
| TryFoldWith { |
| base, |
| item, |
| fold_op, |
| } |
| } |
| } |
| |
| /// `TryFoldWith` is an iterator that applies a function over an iterator producing a single value. |
| /// This struct is created by the [`try_fold_with()`] method on [`ParallelIterator`] |
| /// |
| /// [`try_fold_with()`]: trait.ParallelIterator.html#method.try_fold_with |
| /// [`ParallelIterator`]: trait.ParallelIterator.html |
| #[must_use = "iterator adaptors are lazy and do nothing unless consumed"] |
| #[derive(Clone)] |
| pub struct TryFoldWith<I, U: Try, F> { |
| base: I, |
| item: U::Ok, |
| fold_op: F, |
| } |
| |
| impl<I: ParallelIterator + Debug, U: Try, F> Debug for TryFoldWith<I, U, F> |
| where |
| U::Ok: Debug, |
| { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| f.debug_struct("TryFoldWith") |
| .field("base", &self.base) |
| .field("item", &self.item) |
| .finish() |
| } |
| } |
| |
| impl<U, I, F> ParallelIterator for TryFoldWith<I, U, F> |
| where |
| I: ParallelIterator, |
| F: Fn(U::Ok, I::Item) -> U + Sync + Send, |
| U: Try + Send, |
| U::Ok: Clone + Send, |
| { |
| type Item = U; |
| |
| fn drive_unindexed<C>(self, consumer: C) -> C::Result |
| where |
| C: UnindexedConsumer<Self::Item>, |
| { |
| let consumer1 = TryFoldWithConsumer { |
| base: consumer, |
| item: self.item, |
| fold_op: &self.fold_op, |
| }; |
| self.base.drive_unindexed(consumer1) |
| } |
| } |
| |
| struct TryFoldWithConsumer<'c, C, U: Try, F> { |
| base: C, |
| item: U::Ok, |
| fold_op: &'c F, |
| } |
| |
| impl<'r, U, T, C, F> Consumer<T> for TryFoldWithConsumer<'r, C, U, F> |
| where |
| C: Consumer<U>, |
| F: Fn(U::Ok, T) -> U + Sync, |
| U: Try + Send, |
| U::Ok: Clone + Send, |
| { |
| type Folder = TryFoldFolder<'r, C::Folder, U, F>; |
| type Reducer = C::Reducer; |
| type Result = C::Result; |
| |
| fn split_at(self, index: usize) -> (Self, Self, Self::Reducer) { |
| let (left, right, reducer) = self.base.split_at(index); |
| ( |
| TryFoldWithConsumer { |
| base: left, |
| item: self.item.clone(), |
| ..self |
| }, |
| TryFoldWithConsumer { |
| base: right, |
| ..self |
| }, |
| reducer, |
| ) |
| } |
| |
| fn into_folder(self) -> Self::Folder { |
| TryFoldFolder { |
| base: self.base.into_folder(), |
| result: Ok(self.item), |
| fold_op: self.fold_op, |
| } |
| } |
| |
| fn full(&self) -> bool { |
| self.base.full() |
| } |
| } |
| |
| impl<'r, U, T, C, F> UnindexedConsumer<T> for TryFoldWithConsumer<'r, C, U, F> |
| where |
| C: UnindexedConsumer<U>, |
| F: Fn(U::Ok, T) -> U + Sync, |
| U: Try + Send, |
| U::Ok: Clone + Send, |
| { |
| fn split_off_left(&self) -> Self { |
| TryFoldWithConsumer { |
| base: self.base.split_off_left(), |
| item: self.item.clone(), |
| ..*self |
| } |
| } |
| |
| fn to_reducer(&self) -> Self::Reducer { |
| self.base.to_reducer() |
| } |
| } |