D-programming-unary-operators-overloading
提供:Dev Guides
単項演算子のオーバーロード
次の表に、単項演算子のリストとその目的を示します。
Function Name | Operator | Purpose |
---|---|---|
opUnary | - | Negative of (numeric complement of) |
opUnary | + | The same value as (or, a copy of) |
opUnary | ~ | Bitwise negation |
opUnary | * | Access to what it points to |
opUnary | ++ | Increment |
opUnary | — | Decrement |
以下に、バイナリ演算子をオーバーロードする方法を説明する例を示します。
import std.stdio;
class Box {
public:
double getVolume() {
return length* breadth * height;
}
void setLength( double len ) {
length = len;
}
void setBreadth( double bre ) {
breadth = bre;
}
void setHeight( double hei ) {
height = hei;
}
Box opUnary(string op)() {
if(op == "++") {
Box box = new Box();
box.length = this.length + 1;
box.breadth = this.breadth + 1 ;
box.height = this.height + 1;
return box;
}
}
private:
double length; //Length of a box
double breadth; //Breadth of a box
double height; //Height of a box
};
//Main function for the program
void main( ) {
Box Box1 = new Box(); //Declare Box1 of type Box
Box Box2 = new Box(); //Declare Box2 of type Box
double volume = 0.0; //Store the volume of a box here
//box 1 specification
Box1.setLength(6.0);
Box1.setBreadth(7.0);
Box1.setHeight(5.0);
//volume of box 1
volume = Box1.getVolume();
writeln("Volume of Box1 : ", volume);
//Add two object as follows:
Box2 = ++Box1;
//volume of box2
volume = Box2.getVolume();
writeln("Volume of Box2 : ", volume);
}
上記のコードをコンパイルして実行すると、次の結果が生成されます-
Volume of Box1 : 210
Volume of Box2 : 336