{{
        call_a_or_b_on_tail!(
            (a: compute_len, b: zero), call b: only the terminal rules care.
        )
}}
{{
        call_a_or_b_on_tail!(
            (a: compute_len, b: zero), call a: some ninety one!
        )
}}
{{
        call_a_or_b_on_tail!(
            (a: compute_len, b: zero), call a: some ninety "(\"()"nine!
        )
}}

{{ call_a_or_b_on_tail!((a: compute_len, b: zero), call b: only the terminal rules care.) }}
{{ call_a_or_b_on_tail!((a: compute_len, b: zero), call a: some ninety one!) }}
{{ call_a_or_b_on_tail!((a: compute_len, b: zero), call a: some ninety "(\"()"nine!) }}

Reformat test for better readability
Reformat test for better readability
