1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
//
//! Map implementation.
//!
//! Will be automatically included when including `filter::Filter`, so importing this module
//! shouldn't be necessary.
//!
use std::marker::PhantomData;
use std::borrow::Borrow;
use filter::Filter;
#[must_use = "filters are lazy and do nothing unless consumed"]
#[derive(Clone)]
pub struct MapInput<F, M, FT, B>(F, M, PhantomData<FT>, PhantomData<B>);
impl<F, M, FT, B> MapInput<F, M, FT, B> {
pub fn new(a: F, m: M) -> MapInput<F, M, FT, B> {
MapInput(a, m, PhantomData, PhantomData)
}
}
impl<FT, F, T, B, M> Filter<T> for MapInput<F, M, FT, B>
where F: Filter<FT>,
B: Borrow<FT> + Sized,
M: Fn(&T) -> B
{
fn filter(&self, e: &T) -> bool {
self.0.filter(self.1(e).borrow())
}
}
|
