Parent implementation different to child implementation

I have the following interface:

struct IFilter
{
    virtual enterClass(ClassData&, int recursiveLevel) = 0;
    virtual enterStructure(ClassData&, int recursiveLevel) = 0;
    virtual enterVariable(ClassData&, int recursiveLevel) = 0;
    virtual enterFunction(ClassData&, int recursiveLevel) = 0;
};

And here is an example of an implementation:

struct ReadOnlyFilter: public IFilter
{
    virtual enterClass(ClassData& classData, int recursiveLevel)
    {
        if(recursiveLevel==0 || classData->isReadondOnly())
        {
            this.out << "Class " << classData->name() << "\n{";
        }
    }

So items can contain classes, structs, variables and functions. A class or struct can contain items as children and grandchildren and so on. The class ReadOnlyFilter is used by a function which will loop recursively over all of the children and grandchildren etc of an item. The recursiveLevel is incremented as we go deeper and deeper, like this:

Class c (recursiveLevel=0)
{
    Variable v1 (recursiveLevel=1)
    Class cChild (recursiveLevel=1)
    {
       Class cGrandChild (recursiveLevel=2)

All my implementations have one thing in common: they should always write to this.out if the recursiveLevel is zero. This is why I have if(recursiveLevel==0 || in my code. This results in ifs everywhere in my code.

To solve this, I was thinking of doing something like this instead and was wondering if you think this is a good solution:

(I'm using C++98 and Boost)

struct IFilter
{
    virtual enterClass(ClassData&, int recursiveLevel) = 0;
    virtual enterStructure(ClassData&, int recursiveLevel) = 0;
    virtual enterVariable(ClassData&, int recursiveLevel) = 0;
    virtual enterFunction(ClassData&, int recursiveLevel) = 0;

    virtual enterChildClass(ClassData&, int recursiveLevel) = 0;
    virtual enterChildStructure(ClassData&, int recursiveLevel) = 0;
    virtual enterChildVariable(ClassData&, int recursiveLevel) = 0;
    virtual enterChildFunction(ClassData&, int recursiveLevel) = 0;
};

struct BaseFilter: public IStyler
{
    virtual enterClass(ClassData& classData, int recursiveLevel)
    {
        out << "Class " << classData->name() << "\n{";
    }

struct ReadOnlyFilter: public BaseFilter
{
    virtual enterChildClass(ClassData& classData, int recursiveLevel)
    {
        if(classData->isReadondOnly())
        {
            enterClass(classData, recursiveLevel);
        }
    }