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Use a template to overcome the disadvantage of a base class?

Obviously, standard containers do not have a common base class or common interface, although the method names are uniform.

Problem: I have to fill the container with a collection of objects of a unique type. The container may be std::list, a std::vectoror, std::dequeand possibly some other custom container. Is the following code the best solution?

# include <string>
# include <iostream>
# include <list>
# include <vector>
# include <deque>

/*
 * Fill a container with two strings. The container
 * must expose the `clear` and `push_back` methods.
 */
template<typename T>
void f(T & t)
{
    t.clear() ;

    t.push_back("Alice") ;
    t.push_back("Bob") ;
}

int main(int, char*[])
{
    std::list<std::string>    l ;
    std::vector<std::string>  v ;
    std::deque<std::string>   q ;

    f(l) ;   // fill the list
    f(v) ;   // fill the vector
    f(q) ;   // fill the double-ended queue

    // possibly anything with `clear` and `push_back` methods
    // can be filled with `f`

    return 0 ;
}

Thanks for any advice!

EDIT

Here is an example that I illustrated with help fin my first post:

struct AudioFormat
{
    uint32_t   samplerate ;   // Sampling frequency
    uint8_t    channels ;     // The number of channels
    uint8_t    bitdepth ;     // The number of bits per sample
} ;

class AudioDevice
{
    // many stuff skipped
    public :
      /*
       * Fills the container with available audio formats handled properly by the device
       */
      void GetSupportedAudioFormats(std::list<AudioFormat> &) ;
    // many stuff skipped
} ;

I am looking for a better way to declare GetSupportedFormatsso that it can handle many other containers, not just std::lists. This is the point of my first post.

+5
3

:

/*
 * Fill a container with two strings. The container
 * must expose the `clear` and `push_back` methods.
 */
template<typename T>
void f(T & t)
{
    t.clear() ;

    std::insert_iterator<T> it(t, t.end());
    *it++ = "Alice";
    *it++ = "Bob";
}

: clear insert, std::set, . , , std::insert_iterator .

+6

.

"STL" std::back_inserter

char const* names[2] = { "Alice", "Bob" };

std::list<std::string> l;
std::vector<std::string> v;
std::deque<std::string> q;  

std::copy(names, names+2, std::back_inserter(l));
std::copy(names, names+2, std::back_inserter(v));
std::copy(names, names+2, std::back_inserter(q));
+3

clear() add()

class ContainerIterface
{
public:
  virtual void clear() = 0;
  virtual void add(const UniqueType &e) = 0;
};

-

template <typename Container>
class TemplatedContainer : public ContainerIntarface {
  virtual void clear() {c_.clear();}
  virtual void add(const UniqueType &e) {std::inserter(c_, c_.end()) = e;}

private:
  Container c_;
};

, . , temaplate, , (std::vector, std::vector<UniqueType>)

+1

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