Error: bad argument count - received 0 but expected 1: #<procedure (? value)>

        Call history:

        <eval>    (+ c cv)
        <eval>    (+ a av)
        <eval>    (+ b bv)
        <eval>    (+ c cv)
        <eval>    (+ a av)
        <eval>    (+ b bv)
        <eval>    (+ c cv)
        <eval>    (+ a av)
        <eval>    (+ b bv)
        <eval>    (+ c cv)
        <eval>    (+ a av)
        <eval>    (+ b bv)
        <eval>    (+ c cv)
        <eval>    (+ a av)
        <eval>    (+ b bv)
        <eval>    (+ c cv)      <--