c++ - How to inherit a member function so that it always returns a reference to the derived instance? -

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i'm working on iterator family, iterator classes x have x& operator++() {++x; return *this} in common, seems idea place in common base class. unfortunately, return type changes, since should return reference derived class.

the following illustrates problem. f() work, workarounds come g() , h(), not satisfactory:

struct {     a& f() {return *this;}      template <typename t>     t& g() {return *(t*)this;}      template <typename t>     t& h(t& unused) {return *(t*)this;} };  struct b : {     int x;     b(int x) : x(x) {} };  int main() {     b b(12);      //b b1 = b.f();   // error: conversion 'a' non-scalar type 'b' requested      b b2 = b.g<b>();  // works     b b3 = b.h(b);    // works }

is there way make b b1 = b.f(); work? maybe using c++11 features?

use crtp:

template<class derived> struct {     derived& f() {return static_cast<derived&>(*this);} };  struct b : a<b> {     int x;     b(int x) : x(x) {} };

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