syntax_data: {"ast_node_type":"other","tokens":[{"end":62,"kind":"keyword","start":0,"text":"Ok(Some(c))"}]}
source_snippet:             Ok(Some(c)) => self.evaluate_candidate(stack, &c),
context_before:         match self.candidate_from_obligation(stack) {
context_after:             Ok(None) => Ok(EvaluatedToAmbig),