syntax_data: {"ast_node_type":"other","tokens":[{"end":61,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:             // the arms are an uninhabited type. Which is OK.
context_before:             // Unreachable patterns in try and await expressions occur when one of
context_after:             hir::MatchSource::AwaitDesugar | hir::MatchSource::TryDesugar(_) => {}