syntax_data: {"ast_node_type":"other","tokens":[{"end":96,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                 // This is only reachable with unsatisfiable predicates. For example, if we have
context_before:             } else {
context_after:                 // `u8: Iterator`, then we can't compute the layout of `<u8 as Iterator>::Item`.