syntax_data: {"ast_node_type":"other","tokens":[{"end":44,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                 // `ExprKind::Borrow` above.
context_before:                 // See the notes for `ExprKind::Array` in `as_rvalue` and for
context_after:                 let is_union = adt_def.is_union();