syntax_data: {"ast_node_type":"other","tokens":[{"end":68,"kind":"keyword","start":0,"text":"///"}]}
source_snippet: /// - CK represents the *closure kind* (Fn vs FnMut vs FnOnce). This
context_before: ///   in scope on the function that defined the closure,
context_after: ///   is rather hackily encoded via a scalar type. See