Approach for removal of comments with syn crate

commentvisitor.rs

struct CommentRemove;

impl VisitMut for CommentRemove {
    fn visit_attribute_mut(&mut self, node: &mut Attribute) {
        // identify comments
        if node.path.is_ident("doc")  {
            println!("{:?}", node.tokens);
            println!("{:?}", node.path);
            // can you "null" out the Attribute in some way so that the comments are removed when you transform back into Rust text source?
            // or is there a different approach?
            node = &mut Attribute{
                bracket_token: None,
                pound_token: None,
                style: None,
                path: None,
                tokens: None,
            };
        }
        visit_mut::visit_attribute_mut(self, node);
    }
}

https://github.com/SOF3/portrait/blob/0.3.0/codegen/src/util.rs#L151

You can use #[cfg(all())].