puroro/internal/
utils.rs

1// Copyright 2021 Google LLC
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//      http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use ::std::borrow::Borrow;
16use ::std::marker::PhantomData;
17
18pub struct BorrowedIter<B: ?Sized, I>(I, PhantomData<B>);
19impl<B: ?Sized, I> BorrowedIter<B, I> {
20    pub fn new(iter: I) -> Self {
21        Self(iter, PhantomData)
22    }
23}
24impl<'a, B, I, T> Iterator for BorrowedIter<B, I>
25where
26    I: Iterator<Item = &'a T>,
27    T: 'a + Borrow<B>,
28    B: 'a + ?Sized,
29{
30    type Item = &'a B;
31    fn next(&mut self) -> Option<Self::Item> {
32        self.0.next().map(|owned| owned.borrow())
33    }
34}
puroro/internal/utils.rs

puroro/internal/
utils.rs
