{"ast_node_type":"other","tokens":[{"end":17,"kind":"keyword","start":0,"text":"expect![["}]}
        expect![[
        "struct Result<T, E> {} struct Option<T> {} fn f1() -> Result<(), Vec<Error>> {foo()}",
            "struct Result<T, E> {} struct Option<T> {} fn f1() -> Option<Vec<Error>> {foo()}"