syntax_data: {"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"nested_obligations.into_iter().chain(obligations),"}]}
source_snippet:                     nested_obligations.into_iter().chain(obligations),
context_before:                     TraitObligationStackList::empty(&ProvisionalEvaluationCache::default()),
context_after:                 )