C + + Telescoping constructor is not supported until c++11

Telescoping Constructor:see effective Java 2nd Edition Item 2

If you want to use telescoping constructor but your compiler does not support C++11 standards, you can use default par Ameter instead, see Code Snippets ' main.cpp ', ' Box.h ', ' Box.cpp '.

If your compiler supports C++11 standards, the syntax of telescoping are shown in code snippet ' Box2.h ' and ' Box2.cpp ', and You might need to use '-std=c++11 ' parameter if you're compiling your source code.

For-now, I-d like-to-use default parameter.

Main.cpp

1#include"Box.h"2 3 intMain ()4 {5 box box;6 box.print ();7Box Box2 (1);8 box2.print ();9Box Box3 (1,'A');Ten box3.print (); OneBox Box4 (1,'A',1.88); A box4.print (); -     return 0; -}

Box.h

1 #ifndef Box_h2 #defineBox_h3 4 classBox5 {6      Public:7Box (Const int&_a =0,Const Char&_b ='M',Const Double&_c =0.99);8~Box ();9         voidprint ();Ten  One     Private: A         intA; -         Charb; -         DoubleC; the }; -  - #endif //Box_h

Box.cpp

1#include"Box.h"2 3#include <iostream>4 5 using namespacestd;6 7Box::box (Const int&_a,Const Char&_b,Const Double&_c)8 : A (_a), B (_b), C (_c)9 {Ten  One } A  -box::~Box () - { the  - } -  - voidBox::p rint () { +cout <<"A ="<< a <<", B ="<< b <<", C ="<< C <<Endl; -}

Box2.h

1 #ifndef Box_h2 #defineBox_h3 4 classBox5 {6      Public:7Box (Const int&_a,Const Char&_b,Const Double&_c);8Box (Const int&_a,Const Char&_b);9Box (Const int&_a);Ten Box (); One~Box (); A         voidprint (); -  -     Private: the         intA; -         Charb; -         DoubleC; - }; +  - #endif //Box_h

Box2.cpp

1#include"Box.h"2 3#include <iostream>4 5 using namespacestd;6 7Box::box (Const int&_a,Const Char&_b,Const Double&_c)8 : A (_a), B (_b), C (_c)9 {Ten  One } A  -Box::box (Const int&_a,Const Char&_b) -: Box (_a, _b,0.99) the { -  - } -  +Box::box (Const int&_a) -: Box (_a,'M') + { A  at } -  - Box::box () -: Box (0) - { -  in } -  tobox::~Box () + { -  the } *  $ voidBox::p rint () {Panax Notoginsengcout <<"A ="<< a <<", B ="<< b <<", C ="<< C <<Endl; -}

C + + Telescoping constructor is not supported until c++11