Method visit_pre_post

src/expr/src/visit.rs:410–436

(&self, pre: &mut F1, post: &mut F2)

        Ok(())
    }
    fn visit_pre_post<F1, F2>(&self, pre: &mut F1, post: &mut F2)
    where
        F1: FnMut(&Self) -> Option<Vec<&Self>>,
        F2: FnMut(&Self),
    {
        use VisitAction::*;
        let mut stack = vec![Enter(self)];
        while let Some(action) = stack.pop() {
            match action {
                Enter(elt) => {
                    stack.push(Leave(elt));
                    if let Some(children) = pre(elt) {
                        for child in children.into_iter().rev() {
                            stack.push(Enter(child));
                        }
                    } else {
                        for child in elt.children().rev() {
                            stack.push(Enter(child));
                        }
                    }
                }
                Leave(elt) => {
                    post(elt);
                }
            }
        }
    }

    #[allow(clippy::as_conversions)]
    fn visit_mut_pre_post<F1, F2>(&mut self, pre: &mut F1, post: &mut F2)