operators

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[编辑] 运算符重载

[编辑] 语法

[编辑] 解释

• <类型> /（s）的变量的类型.

  Original:

  <type> is/are the type(s) of the variables.

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• <op>是在特定的操作（例如+，+=，<<，>>，&&，||，%等）.

  Original:

  <op> is the particular operator (e.g. +, +=, <<, >>, &&, ||, %, etc.).

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• 与<params> /（s）的所需的参数的名称（取决于操作员）.

  Original:

  <params> is/are the name(s) of the required parameters (depends on the operator).

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[编辑] 限制

• 您不能创建新的运营商，如**或&|.

  Original:

  You cannot create new operators such as ** or &|.

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• 并非所有的运营商都可以被重载

  Original:

  Not all operators can be overloaded

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• 一些运算符只能重载为类非静态成员

  Original:

  Some operators can only be overloaded as non-static class members

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• 不使用重载运算符的短路计算

  Original:

  Short-circuit evaluation doesn't work with overloaded operators

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[编辑] 操作者呼叫

a+b

operator+(a,b)

[编辑] 为例

#include <iostream>
 using namespace std;
 
 class Fraction{
   private:
     int numerator, denominator;
 
   public:
     Fraction(int n, int d): numerator(n), denominator(d) {}
   // Note that the keyword operator combined with an actual
   // operator is used as the function name
   friend ostream& operator<<(ostream&, Fraction&);
 };
 
 ostream& operator<<(ostream& out, Fraction& f){
   out << f.numerator << '/' << f.denominator;
   return out;
 }
 
 int main(){
   Fraction f1(3, 8);
   Fraction f2(1, 2);
 
   cout << f1 << endl;
   cout << 3 << ' ' << f2 << endl;
 
   return 0;
 }

3/8
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[编辑] 见也

• 运算符优先级
• 替代运算符的语法