syntax_data: {"ast_node_type":"other","tokens":[{"end":59,"kind":"keyword","start":0,"text":"(($self:ident,"}]}
source_snippet:     (($self:ident, $p:ident): $($ty:ty $print:block)+) => {
context_before: macro_rules! define_print_and_forward_display {
context_after:         define_print!(($self, $p): $($ty $print)*);