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

use super::*;

impl<'i, N> Iterator for TokenTreeFilterTag<'i, N>
where
    N: YggdrasilNode<'i>,
{
    type Item = Result<N, YggdrasilError<N::Rule>>;

    fn next(&mut self) -> Option<Self::Item> {
        let pair = self.tree.next()?;
        if self.target.eq(pair.get_tag()) { Some(N::from_pair(pair)) } else { self.next() }
    }
}

impl<'i, N> Iterator for TokenTreeFilterRule<'i, N>
where
    N: YggdrasilNode<'i>,
    <N as YggdrasilNode<'i>>::Rule: Clone,
{
    type Item = Result<N, YggdrasilError<N::Rule>>;

    fn next(&mut self) -> Option<Self::Item> {
        let pair = self.tree.next()?;
        if pair.get_rule().get_enum().eq(&self.target.get_enum()) {
            return Some(N::from_pair(pair));
        }
        self.next()
    }
}