imag/lib/entry/libimagentryutil/src/iter.rs

//
// imag - the personal information management suite for the commandline
// Copyright (C) 2015-2019 Matthias Beyer <mail@beyermatthias.de> and contributors
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; version
// 2.1 of the License.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
//

use filters::filter::Filter;

pub trait NextWhere<T> {
    type Item;

    fn next_where<F>(&mut self, f: &F) -> Option<Self::Item>
        where F: Filter<T>;
}

impl<T, I> NextWhere<T> for I
    where I: Iterator<Item = T>
{
    type Item = T;

    fn next_where<F>(&mut self, f: &F) -> Option<Self::Item>
        where F: Filter<T>
    {
        while let Some(next) = self.next() {
            if f.filter(&next) {
                return Some(next);
            }
        }
        None
    }
}