Re: Abstract classes, multiple inheritance, and implemention question

"Igor Tandetnik" <>
Sat, 21 Jun 2008 18:13:22 -0400
"Bogdan" <> wrote in message

I have 2 abstract structs as follows:

struct s1 {
   virtual void f1() = 0;
   virtual void f2() = 0;

struct s2 : public s1{
   virtual void f3() = 0;

I also have 2 implementation classes:

class s1imp : pubic s1 {
   virtual void f1() {}
   virtual void f2() {}

class s2imp : public s2 {
  virtual void f1() {}
  virtual void f2() {}
  virtual void f3() {}

Is there a way for class s2imp to derive from s1imp to take advantage
of its implementation of s1 (i.e. f1() and f2()) and provide the
implementation of f3() only?

template <typename Itf>
class s1imp_t : public Itf {
   virtual void f1() {}
   virtual void f2() {}

class s1imp : public s1imp_t<s1> {};
class s2imp : public s1imp_t<s2> {
    virtual void f3() {}

With best wishes,
    Igor Tandetnik

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