Case

case can be used as statement. The right-hand of arm is statement.

module ModuleA {
    let a: logic<10> = 1;
    var b: logic<10>;

    always_comb {
        case a {
            0: b = 1;
            1: b = 2;
            2: {
                   b = 3;
                   b = 3;
                   b = 3;
               }
            default: b = 4;
        }
    }
}