{"ast_node_type":"variable","tokens":[{"end":57,"kind":"keyword","start":0,"text":"let"}]}
        let (func, subst) = match callee.kind(Interner) {
    fn check_legacy_const_generics(&mut self, callee: Ty, args: &[ExprId]) -> Box<[u32]> {
            TyKind::FnDef(fn_id, subst) => {