/rust/registry/src/index.crates.io-1949cf8c6b5b557f/rayon-1.10.0/src/iter/inspect.rs

Source
use super::plumbing::*;
use super::*;

use std::fmt::{self, Debug};
use std::iter;

/// `Inspect` is an iterator that calls a function with a reference to each
/// element before yielding it.
///
/// This struct is created by the [`inspect()`] method on [`ParallelIterator`]
///
/// [`inspect()`]: trait.ParallelIterator.html#method.inspect
/// [`ParallelIterator`]: trait.ParallelIterator.html
#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
#[derive(Clone)]
pub struct Inspect<I: ParallelIterator, F> {
    base: I,
    inspect_op: F,
}

impl<I: ParallelIterator + Debug, F> Debug for Inspect<I, F> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Inspect").field("base", &self.base).finish()
    }
}

impl<I, F> Inspect<I, F>
where
    I: ParallelIterator,
{
    /// Creates a new `Inspect` iterator.
    pub(super) fn new(base: I, inspect_op: F) -> Self {
        Inspect { base, inspect_op }
    }
}

impl<I, F> ParallelIterator for Inspect<I, F>
where
    I: ParallelIterator,
    F: Fn(&I::Item) + Sync + Send,
{
    type Item = I::Item;

    fn drive_unindexed<C>(self, consumer: C) -> C::Result
    where
        C: UnindexedConsumer<Self::Item>,
    {
        let consumer1 = InspectConsumer::new(consumer, &self.inspect_op);
        self.base.drive_unindexed(consumer1)
    }

    fn opt_len(&self) -> Option<usize> {
        self.base.opt_len()
    }
}

impl<I, F> IndexedParallelIterator for Inspect<I, F>
where
    I: IndexedParallelIterator,
    F: Fn(&I::Item) + Sync + Send,
{
    fn drive<C>(self, consumer: C) -> C::Result
    where
        C: Consumer<Self::Item>,
    {
        let consumer1 = InspectConsumer::new(consumer, &self.inspect_op);
        self.base.drive(consumer1)
    }

    fn len(&self) -> usize {
        self.base.len()
    }

    fn with_producer<CB>(self, callback: CB) -> CB::Output
    where
        CB: ProducerCallback<Self::Item>,
    {
        return self.base.with_producer(Callback {
            callback,
            inspect_op: self.inspect_op,
        });

        struct Callback<CB, F> {
            callback: CB,
            inspect_op: F,
        }

        impl<T, F, CB> ProducerCallback<T> for Callback<CB, F>
        where
            CB: ProducerCallback<T>,
            F: Fn(&T) + Sync,
        {
            type Output = CB::Output;

            fn callback<P>(self, base: P) -> CB::Output
            where
                P: Producer<Item = T>,
            {
                let producer = InspectProducer {
                    base,
                    inspect_op: &self.inspect_op,
                };
                self.callback.callback(producer)
            }
        }
    }
}

/// ////////////////////////////////////////////////////////////////////////

struct InspectProducer<'f, P, F> {
    base: P,
    inspect_op: &'f F,
}

impl<'f, P, F> Producer for InspectProducer<'f, P, F>
where
    P: Producer,
    F: Fn(&P::Item) + Sync,
{
    type Item = P::Item;
    type IntoIter = iter::Inspect<P::IntoIter, &'f F>;

    fn into_iter(self) -> Self::IntoIter {
        self.base.into_iter().inspect(self.inspect_op)
    }

    fn min_len(&self) -> usize {
        self.base.min_len()
    }

    fn max_len(&self) -> usize {
        self.base.max_len()
    }

    fn split_at(self, index: usize) -> (Self, Self) {
        let (left, right) = self.base.split_at(index);
        (
            InspectProducer {
                base: left,
                inspect_op: self.inspect_op,
            },
            InspectProducer {
                base: right,
                inspect_op: self.inspect_op,
            },
        )
    }

    fn fold_with<G>(self, folder: G) -> G
    where
        G: Folder<Self::Item>,
    {
        let folder1 = InspectFolder {
            base: folder,
            inspect_op: self.inspect_op,
        };
        self.base.fold_with(folder1).base
    }
}

/// ////////////////////////////////////////////////////////////////////////
/// Consumer implementation

struct InspectConsumer<'f, C, F> {
    base: C,
    inspect_op: &'f F,
}

impl<'f, C, F> InspectConsumer<'f, C, F> {
    fn new(base: C, inspect_op: &'f F) -> Self {
        InspectConsumer { base, inspect_op }
    }
}

impl<'f, T, C, F> Consumer<T> for InspectConsumer<'f, C, F>
where
    C: Consumer<T>,
    F: Fn(&T) + Sync,
{
    type Folder = InspectFolder<'f, C::Folder, 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);
        (
            InspectConsumer::new(left, self.inspect_op),
            InspectConsumer::new(right, self.inspect_op),
            reducer,
        )
    }

    fn into_folder(self) -> Self::Folder {
        InspectFolder {
            base: self.base.into_folder(),
            inspect_op: self.inspect_op,
        }
    }

    fn full(&self) -> bool {
        self.base.full()
    }
}

impl<'f, T, C, F> UnindexedConsumer<T> for InspectConsumer<'f, C, F>
where
    C: UnindexedConsumer<T>,
    F: Fn(&T) + Sync,
{
    fn split_off_left(&self) -> Self {
        InspectConsumer::new(self.base.split_off_left(), self.inspect_op)
    }

    fn to_reducer(&self) -> Self::Reducer {
        self.base.to_reducer()
    }
}

struct InspectFolder<'f, C, F> {
    base: C,
    inspect_op: &'f F,
}

impl<'f, T, C, F> Folder<T> for InspectFolder<'f, C, F>
where
    C: Folder<T>,
    F: Fn(&T),
{
    type Result = C::Result;

    fn consume(self, item: T) -> Self {
        (self.inspect_op)(&item);
        InspectFolder {
            base: self.base.consume(item),
            inspect_op: self.inspect_op,
        }
    }

    fn consume_iter<I>(mut self, iter: I) -> Self
    where
        I: IntoIterator<Item = T>,
    {
        self.base = self
            .base
            .consume_iter(iter.into_iter().inspect(self.inspect_op));
        self
    }

    fn complete(self) -> C::Result {
        self.base.complete()
    }

    fn full(&self) -> bool {
        self.base.full()
    }
}

Coverage Report

Created: 2025-11-28 06:44

Line	Count	Source
1		use super::plumbing::*;
2		use super::*;
3
4		use std::fmt::{self, Debug};
5		use std::iter;
6
7		/// `Inspect` is an iterator that calls a function with a reference to each
8		/// element before yielding it.
9		///
10		/// This struct is created by the [`inspect()`] method on [`ParallelIterator`]
11		///
12		/// [`inspect()`]: trait.ParallelIterator.html#method.inspect
13		/// [`ParallelIterator`]: trait.ParallelIterator.html
14		#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
15		#[derive(Clone)]
16		pub struct Inspect<I: ParallelIterator, F> {
17		base: I,
18		inspect_op: F,
19		}
20
21		impl<I: ParallelIterator + Debug, F> Debug for Inspect<I, F> {
22	0	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
23	0	f.debug_struct("Inspect").field("base", &self.base).finish()
24	0	}
25		}
26
27		impl<I, F> Inspect<I, F>
28		where
29		I: ParallelIterator,
30		{
31		/// Creates a new `Inspect` iterator.
32	0	pub(super) fn new(base: I, inspect_op: F) -> Self {
33	0	Inspect { base, inspect_op }
34	0	}
35		}
36
37		impl<I, F> ParallelIterator for Inspect<I, F>
38		where
39		I: ParallelIterator,
40		F: Fn(&I::Item) + Sync + Send,
41		{
42		type Item = I::Item;
43
44	0	fn drive_unindexed<C>(self, consumer: C) -> C::Result
45	0	where
46	0	C: UnindexedConsumer<Self::Item>,
47		{
48	0	let consumer1 = InspectConsumer::new(consumer, &self.inspect_op);
49	0	self.base.drive_unindexed(consumer1)
50	0	}
51
52	0	fn opt_len(&self) -> Option<usize> {
53	0	self.base.opt_len()
54	0	}
55		}
56
57		impl<I, F> IndexedParallelIterator for Inspect<I, F>
58		where
59		I: IndexedParallelIterator,
60		F: Fn(&I::Item) + Sync + Send,
61		{
62	0	fn drive<C>(self, consumer: C) -> C::Result
63	0	where
64	0	C: Consumer<Self::Item>,
65		{
66	0	let consumer1 = InspectConsumer::new(consumer, &self.inspect_op);
67	0	self.base.drive(consumer1)
68	0	}
69
70	0	fn len(&self) -> usize {
71	0	self.base.len()
72	0	}
73
74	0	fn with_producer<CB>(self, callback: CB) -> CB::Output
75	0	where
76	0	CB: ProducerCallback<Self::Item>,
77		{
78	0	return self.base.with_producer(Callback {
79	0	callback,
80	0	inspect_op: self.inspect_op,
81	0	});
82
83		struct Callback<CB, F> {
84		callback: CB,
85		inspect_op: F,
86		}
87
88		impl<T, F, CB> ProducerCallback<T> for Callback<CB, F>
89		where
90		CB: ProducerCallback<T>,
91		F: Fn(&T) + Sync,
92		{
93		type Output = CB::Output;
94
95	0	fn callback<P>(self, base: P) -> CB::Output
96	0	where
97	0	P: Producer<Item = T>,
98		{
99	0	let producer = InspectProducer {
100	0	base,
101	0	inspect_op: &self.inspect_op,
102	0	};
103	0	self.callback.callback(producer)
104	0	}
105		}
106	0	}
107		}
108
109		/// ////////////////////////////////////////////////////////////////////////
110
111		struct InspectProducer<'f, P, F> {
112		base: P,
113		inspect_op: &'f F,
114		}
115
116		impl<'f, P, F> Producer for InspectProducer<'f, P, F>
117		where
118		P: Producer,
119		F: Fn(&P::Item) + Sync,
120		{
121		type Item = P::Item;
122		type IntoIter = iter::Inspect<P::IntoIter, &'f F>;
123
124	0	fn into_iter(self) -> Self::IntoIter {
125	0	self.base.into_iter().inspect(self.inspect_op)
126	0	}
127
128	0	fn min_len(&self) -> usize {
129	0	self.base.min_len()
130	0	}
131
132	0	fn max_len(&self) -> usize {
133	0	self.base.max_len()
134	0	}
135
136	0	fn split_at(self, index: usize) -> (Self, Self) {
137	0	let (left, right) = self.base.split_at(index);
138	0	(
139	0	InspectProducer {
140	0	base: left,
141	0	inspect_op: self.inspect_op,
142	0	},
143	0	InspectProducer {
144	0	base: right,
145	0	inspect_op: self.inspect_op,
146	0	},
147	0	)
148	0	}
149
150	0	fn fold_with<G>(self, folder: G) -> G
151	0	where
152	0	G: Folder<Self::Item>,
153		{
154	0	let folder1 = InspectFolder {
155	0	base: folder,
156	0	inspect_op: self.inspect_op,
157	0	};
158	0	self.base.fold_with(folder1).base
159	0	}
160		}
161
162		/// ////////////////////////////////////////////////////////////////////////
163		/// Consumer implementation
164
165		struct InspectConsumer<'f, C, F> {
166		base: C,
167		inspect_op: &'f F,
168		}
169
170		impl<'f, C, F> InspectConsumer<'f, C, F> {
171	0	fn new(base: C, inspect_op: &'f F) -> Self {
172	0	InspectConsumer { base, inspect_op }
173	0	}
174		}
175
176		impl<'f, T, C, F> Consumer<T> for InspectConsumer<'f, C, F>
177		where
178		C: Consumer<T>,
179		F: Fn(&T) + Sync,
180		{
181		type Folder = InspectFolder<'f, C::Folder, F>;
182		type Reducer = C::Reducer;
183		type Result = C::Result;
184
185	0	fn split_at(self, index: usize) -> (Self, Self, Self::Reducer) {
186	0	let (left, right, reducer) = self.base.split_at(index);
187	0	(
188	0	InspectConsumer::new(left, self.inspect_op),
189	0	InspectConsumer::new(right, self.inspect_op),
190	0	reducer,
191	0	)
192	0	}
193
194	0	fn into_folder(self) -> Self::Folder {
195	0	InspectFolder {
196	0	base: self.base.into_folder(),
197	0	inspect_op: self.inspect_op,
198	0	}
199	0	}
200
201	0	fn full(&self) -> bool {
202	0	self.base.full()
203	0	}
204		}
205
206		impl<'f, T, C, F> UnindexedConsumer<T> for InspectConsumer<'f, C, F>
207		where
208		C: UnindexedConsumer<T>,
209		F: Fn(&T) + Sync,
210		{
211	0	fn split_off_left(&self) -> Self {
212	0	InspectConsumer::new(self.base.split_off_left(), self.inspect_op)
213	0	}
214
215	0	fn to_reducer(&self) -> Self::Reducer {
216	0	self.base.to_reducer()
217	0	}
218		}
219
220		struct InspectFolder<'f, C, F> {
221		base: C,
222		inspect_op: &'f F,
223		}
224
225		impl<'f, T, C, F> Folder<T> for InspectFolder<'f, C, F>
226		where
227		C: Folder<T>,
228		F: Fn(&T),
229		{
230		type Result = C::Result;
231
232	0	fn consume(self, item: T) -> Self {
233	0	(self.inspect_op)(&item);
234	0	InspectFolder {
235	0	base: self.base.consume(item),
236	0	inspect_op: self.inspect_op,
237	0	}
238	0	}
239
240	0	fn consume_iter<I>(mut self, iter: I) -> Self
241	0	where
242	0	I: IntoIterator<Item = T>,
243		{
244	0	self.base = self
245	0	.base
246	0	.consume_iter(iter.into_iter().inspect(self.inspect_op));
247	0	self
248	0	}
249
250	0	fn complete(self) -> C::Result {
251	0	self.base.complete()
252	0	}
253
254	0	fn full(&self) -> bool {
255	0	self.base.full()
256	0	}
257		}