7.8. Overloading comparison operators PDF

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7.8 Overloading comparison operators
Overloading the equality (==) operator
A programmer can overload the equality operator (==) to allow comparing objects of a programmer-defined class for equality. To overload ==, the programmer creates a function named operator== that returns bool and...

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2/19/2021

7.8. Overloading comparison operators

7.8 Overloading comparison operators Overloading the equality (==) operator A programmer can overload the equality operator (==) to allow comparing objects of a programmer-dened class for equality. To overload ==, the programmer creates a function named operator== that returns bool and takes two const reference arguments of the class type for the left-hand-side and right-hand-side operands. Ex: To overload the == operator for a Review class, the programmer denes a function bool operator==(const Review& lhs, const Review& rhs). The programmer must also determine when two objects are considered equal. In the Review class below, two Review objects are equal if the objects have the same rating and comment. PARTICIPATION ACTIVITY

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7.8.1: Overloading the == operator.

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bestReview

bool operator==(const Review& lhs, const Review& rhs) { return (lhs.GetRating() == rhs.GetRating()) && (lhs.GetComment() == rhs.GetComment()); } ( == ) && 5 5 ( "Great" == "Great" ) true && true // ...

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if (myReview == bestReview) { cout currentRating; } // Sort reviews from lowest to highest sort(reviewList.begin(), reviewList.end()); cout...