syntax_data: {"ast_node_type":"other","tokens":[{"end":57,"kind":"keyword","start":0,"text":"(Self::Reachable(x),"}]}
source_snippet:             (Self::Reachable(x), Self::Reachable(y)) => {
context_before:         match (&mut *self, source) {
context_after:                 x.clone_from(&y);