# backup.krb

top_a
    use top($a)
    when
        a($a)

top_b
    use top($_)

a
    # creates context and binds local $a to top $a
    use a($a)
    when
        c($a)
        special.claim_goal()
        check False

c
    # creates context and binds top $a to 44
    use c(44)
