syntax_data: {"ast_node_type":"other","tokens":[{"end":65,"kind":"keyword","start":0,"text":"ty::Placeholder(..)"}]}
source_snippet:         ty::Placeholder(..) => Some(SimplifiedType::Placeholder),
context_before:         ty::UnsafeBinder(_) => Some(SimplifiedType::UnsafeBinder),
context_after:         ty::Param(_) => match treat_params {