syntax_data: {"ast_node_type":"other","tokens":[{"end":37,"kind":"keyword","start":0,"text":"ty::FnPtr(sig_tys,"}]}
source_snippet:         ty::FnPtr(sig_tys, _hdr) => {
context_before:         ty::Tuple(tys) => Some(SimplifiedType::Tuple(tys.len())),
context_after:             Some(SimplifiedType::Function(sig_tys.skip_binder().inputs().len()))