Re: Inherited member( void )const - const to be or not to be

[Eljay Love-Jensen <eljay@xxxxxxxxx>]

Hi Jarmo,

Don't use _CONST ... that's a reserved symbol.

All symbols starting with underscore followed by a capital letter are 
reserved.  All symbols with two underscores in a row anywhere are reserved.

I've fixed your code, works now just fine.  Compiled either way.

BTW:  using the -DCONST=const is preferred.  So much so, that you should 
just have const in the code.  Const correctness should be worked in from 
the beginning.

HTH,
--Eljay

- - - - - - - - -
// Compile #1:  g++ -DCONST=const foo.cpp
// Compile #2:  g++ -DCONST= foo.cpp
#include <cstdio>

class CProvider
{
protected:
    const char* str;
public:
    CProvider(const char* s)
    : str(s)
    {
        printf("CProvider(%s)\n",str);
    }

    void echo() CONST
    {
        printf("CProvider(%s)::echo()\n", str);
    }
};


class CAbstract
{
public:
    CAbstract()
    {
        printf("CAbstract\n");
    }

    virtual ~CAbstract()
    { }

    virtual CProvider CONST* getProvider() CONST = 0;
};


class CAllocated : public CAbstract
{
protected:
    CProvider* ptr;

public:
    CAllocated()
    {
        printf("CAllocated\n");
        ptr = new CProvider("Allocated");
    }

    virtual CProvider CONST* getProvider() CONST
    {
        return ptr;
    }
};


class CInherited : public CAbstract, public CProvider
{
public:
    CInherited()
    : CProvider("Inherited")
    {
        printf("CInherited\n");
    }

    virtual CProvider CONST* getProvider() CONST
    {
        return this;
    }
};


int main()
{
    CAllocated tmp1;
    CInherited tmp2;

    tmp1.getProvider()->echo();
    tmp2.getProvider()->echo();

    CAbstract* pTmp1 = &tmp1;
    CAbstract* pTmp2 = &tmp2;
    pTmp1->getProvider()->echo();
    pTmp2->getProvider()->echo();
}