syntax_data: {"ast_node_type":"other","tokens":[{"end":49,"kind":"keyword","start":0,"text":"canonical_goal:"}]}
source_snippet:     canonical_goal: CanonicalPredicateGoal<'tcx>,
context_before:     tcx: TyCtxt<'tcx>,
context_after: ) -> Result<EvaluationResult, OverflowError> {