syntax_data: {"ast_node_type":"other","tokens":[{"end":76,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:             // their constituent types implement `BikeshedGuaranteedNoDrop`.
context_before:             // Arrays and tuples implement `BikeshedGuaranteedNoDrop` only if
context_after:             ty::Tuple(tys) => {