syntax_data: {"ast_node_type":"other","tokens":[{"end":85,"kind":"keyword","start":0,"text":"(_,"}]}
source_snippet:                 (_, Err(Err::UnknownLayout)) => Answer::No(Reason::DstLayoutUnknown),
context_before:                 (Err(Err::UnknownLayout), _) => Answer::No(Reason::SrcLayoutUnknown),
context_after:                 (Err(Err::NotYetSupported), _) => Answer::No(Reason::SrcIsNotYetSupported),