 Home
 Products
 Integration
 Tutorial
 Barcode FAQ
 Purchase
 Company
ssrs ean 128 CHAP. 91 in Software
CHAP. 91 Recognizing Quick Response Code In None Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications. QR Code 2d Barcode Encoder In None Using Barcode generator for Software Control to generate, create Quick Response Code image in Software applications. OVERLOADING
Reading Denso QR Bar Code In None Using Barcode reader for Software Control to read, scan read, scan image in Software applications. QR Code ISO/IEC18004 Generation In C#.NET Using Barcode generator for .NET framework Control to generate, create QRCode image in .NET applications. OPERATORS
Generating QR Code In .NET Framework Using Barcode generation for ASP.NET Control to generate, create QR Code image in ASP.NET applications. QR Code Drawer In VS .NET Using Barcode maker for .NET framework Control to generate, create QR Code ISO/IEC18004 image in .NET framework applications. EXAMPLE 9.3 Implementation of the Assignment Operator for the Rational Class Rational& Rational: :operator=(const Rational& r) Create Denso QR Bar Code In Visual Basic .NET Using Barcode drawer for .NET Control to generate, create QRCode image in .NET framework applications. DataMatrix Creation In None Using Barcode creator for Software Control to generate, create Data Matrix image in Software applications. num = r.num; den = r.den; return *this; Encode Bar Code In None Using Barcode printer for Software Control to generate, create bar code image in Software applications. Generating GS1 128 In None Using Barcode creation for Software Control to generate, create UCC128 image in Software applications. . Now assignments for the Rat ional
Creating Bar Code In None Using Barcode creation for Software Control to generate, create barcode image in Software applications. Creating UPC Symbol In None Using Barcode encoder for Software Control to generate, create UPCA image in Software applications. Rational x, y, z(22,7); x = y = z; UPC Shipping Container Symbol ITF14 Drawer In None Using Barcode maker for Software Control to generate, create UPC Case Code image in Software applications. Painting UPC  13 In None Using Barcode generator for Excel Control to generate, create European Article Number 13 image in Microsoft Excel applications. class can be chained together: Draw Code 39 In None Using Barcode generator for Office Word Control to generate, create Code39 image in Microsoft Word applications. Encode Data Matrix In None Using Barcode generator for Office Excel Control to generate, create ECC200 image in Microsoft Excel applications. The correct implementation for an overloaded assignment operator in a class
Barcode Printer In C# Using Barcode generation for Visual Studio .NET Control to generate, create barcode image in Visual Studio .NET applications. Painting Barcode In ObjectiveC Using Barcode creator for iPhone Control to generate, create bar code image in iPhone applications. T&i T: :operator=(const T& t) Paint Barcode In None Using Barcode printer for Word Control to generate, create bar code image in Microsoft Word applications. Make Code39 In ObjectiveC Using Barcode drawer for iPhone Control to generate, create ANSI/AIM Code 39 image in iPhone applications. // assign each member datum of t to the // corresponding member datum of the owner return *this; Finally, note that an assignment is different from an initialization, even though they both use the equals sign: Rational x(22,7); Rational y(x); Rational z = x; Rational w; w = x; // this is an initialization // this is an initialization // this is an initialization // this is an assignment An initialization calls the copy constructor. An assignment calls the assignment operator.
9.4 OVERLOADING ARITHMETIC OPERATORS
All programming languages provide the standard arithmetic operators +, , *, and / for numeric types. So it is only natural to define these for userdefined numeric types like the Rat ional class. In older programming languages like C and Pascal, this is done by defining functions like this: Rational product(Rationa1 x, Rational y) x.den*y.den); Rational z(x.num*y.num, return z; This works. But the function has to be called in the conventional way: product(x,y); C++ allows such functions to be defined using the standard arithmetic operator symbols, so that they can be called more naturally: z = x*y; OVERLOADING OPERATORS
[CHAP. 9
Like most operators in C++, the multiplication operator has a function name that uses the reserved word operator: its name is operator*". Using this in place of product" in the code above, we would expect the overloaded function to look something like this: Rational operator*(Rational x, Rational y) x.den*y.den); Rational z(x.num*y.num, return z; But this is not a member function. If it were, we would have to set it up as in Problem 8.50, with only one argument. The operator * function requires two arguments. Since the overloaded arithmetic operators cannot be member functions, they cannot access the private member data num and den. Fortunately, C++ allows an exception to this rule so that we can complete our definitions of the overloaded arithmetic functions. The solution is to declare the function as afriend of the Rational class. A friend function is a nonmember function that is given access to all members of the class within which it is declared. So it has all the privileges of a member function without actually being a member of the class. This attribute is used mostly with overloaded operators. EXAMPLE 9.4 Declaring the Multiplication Operator as a friend Function
Here is the Rat ional friend function: class declaration with the overloaded multiplication operator declared as a
class Rational { friend Rational operator*(const Rational&, public: Rational(int =0, int =l); Rational(const Rational&); Rational& operator=(const Rational&); // other declarations go here private: int num; int den; // other declarations go here const
Rational&); Note that the function prototype is inserted inside the class declaration, above the pub1 note that the two arguments to the function are both passed by constant reference. Now we can implement this nonmember just as we had expected: Rational operator*(const Rational& x, const Rational& t Rational z(x.num * y.num, x.den * y.den); return z; y) ic section. Also
Note that the keyword friend is not used in the function implementation. Also note that the scope resolution prefix Rat i onal : : is not used because this is not a member function. Here is a little program that uses our improved Rational CkkSS: CHAP. 91
OVERLOADING
OPERATORS
EXAMPLE 9.5 The Rat ional Class with Assignment and Multiplication Operators #include main0 Rational x(22,7), y(3,8), z; // assignment operator is called Z = x; tout =c< endl; z.print(); // multiplication operator is called x = y*z; x.print(); tout CC endl; 1 22/7 33/28 "Rationa1.h" Note that the reduce ( ) function was called from within the overloaded multiplication operator to reduce 66/56 to 33/58. (See Example 8.2.) 9.5 OVERLOADING THE ARITHMETIC ASSIGNMENT OPERATORS C++ allows your to combine arithmetic operations with the assignment operator; for example, using x * = Y in place of x = x * Y. These combination operators can all be overloaded for use in your own classes.

