{"ast_node_type":"other","tokens":[{"end":65,"kind":"keyword","start":0,"text":"///"}]}
    /// each type/region parameter to a fresh inference variable.
    /// Given a set of generics defined on a type or impl, returns the generic parameters mapping
    pub fn fresh_args_for_item(&self, span: Span, def_id: DefId) -> GenericArgsRef<'tcx> {