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 {
context_after:         $(impl<'tcx, P: PrettyPrinter<'tcx>> Print<'tcx, P> for $ty {