Given the following classes:

class Foo
{
    struct BarBC
    {
    protected:
        BarBC(uint32_t aKey)
            : mKey(aKey)
              mOtherKey(0)

    public:
        const uint32_t mKey;
        const uint32_t mOtherKey;
    };


    struct Bar : public BarBC
    {
        Bar(uint32_t aKey, uint32_t aOtherKey)
            : BarBC(aKey),
              mOtherKey(aOtherKey) // Compile error here
    };
};

I am getting a compilation error at the point indicated:

error: class `Foo::Bar' does not have any field named `mOtherKey'.

Can anyone explain this? I suspect it's a syntactical problem due to my Bar class being defined within the Foo class, but can't seem to find a way around it.

This is simple public inheritance, so mOtherKey should be accessible from the Bar constructor. Right?

Or is it something to do with the fact that mOtherKey is const and I have already initialised it to 0 in the BarBC constructor?