syntax_data: {"ast_node_type":"other","tokens":[{"end":56,"kind":"keyword","start":0,"text":"BoundRegionConversionTime::HigherRankedType,"}]}
source_snippet:             BoundRegionConversionTime::HigherRankedType,
context_before:             obligation.cause.span,
context_after:             unnormalized_upcast_trait_ref,