🚀 go-pugleaf

Gabriel Sanchez Gutierrez (gsg@sema.es) wrote:
>  Hello,

>  As far as I know, maps are transparent wrt the keys and values stored.
>  I am trying to maintain a map with pointers to member functions. If I access
>  the members through normal pointers, all is Ok. But if I use the dictionary,
>  it seems it is not properly initialized.

>  Any hint?

>  #include <iostream.h>
>  #include <map.h>

>  typedef char* string;

>  class Test {
>      typedef int  (Test::* pGetM) ();
>  public:
>      int a1;
>      int geta1   () {return a1;};

>  public:
>      Test (int a): a1(a) {};
>  };

>  main ()
>  {
>      Test t (5);

>      Test::pGetM f = Test::geta1;
>      
>      map<string, Test::pGetM, less<string> > mapMethods;
>      mapMethods["a1"]  = f; 

>      cout << "Attribut = " << t.a1 << endl
>  	 << "By map   = " << (t.*f)() << endl;

>      cout << "Attribut = " << t.a1 << endl
>  	 << "By map   = " << (t.*mapMethods["a1"])() << endl;
>  }

You are comparing pointers instead of strings. Add

  struct less<string>
  {
	bool operator()(string a, string b) { return strcmp(a, b) < 0; }
  };

and it will work.

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