6     let mut tokens = tokens.iter();  in concat()
7     let mut segments = Vec::new();  in concat()
8     let mut span = None;  in concat()
14                 let mut value = lit.to_string();  in concat()
22                 let mut value = ident.to_string();  in concat()
29                 let Some(TokenTree::Ident(ident)) = tokens.next() else {  in concat()
33                 let (mut value, sp) = segments.pop().expect("expected identifier before modifier");  in concat()
53     let pasted: String = segments.into_iter().map(|x| x.0).collect();  in concat()
59         if let TokenTree::Group(group) = token {  in expand()
60             let delimiter = group.delimiter();  in expand()
61             let span = group.span();  in expand()
62             let mut stream: Vec<_> = group.stream().into_iter().collect();  in expand()
74                 let mut group = Group::new(delimiter, stream.into_iter().collect());  in expand()