Macro quote_tokens_with_context_spanned 

#[doc(hidden)]
macro_rules! quote_tokens_with_context_spanned {
    ($tokens:ident $span:ident
        ($($b3:tt)*) ($($b2:tt)*) ($($b1:tt)*)
        ($($curr:tt)*)
        ($($a1:tt)*) ($($a2:tt)*) ($($a3:tt)*)
    ) => { ... };
}