D Programming - Operators Precedence

Operator precedence determines the grouping of terms in an expression. This affects how an expression is evaluated. Certain operators are given precedence over others.

For example, the multiplication operator has higher precedence than the addition operator.

Let us consider an expression

x = 7 + 3 * 2.

Here, x is assigned 13, not 20. The simple reason is, the operator * has higher precedence than +, hence 3*2 is calculated first and then the result is added into 7.

Here, operators with the highest precedence appear at the top of the table, those with the lowest appear at the bottom. Within an expression, higher precedence operators are evaluated first.

Example

Try the following example to understand the operator precedence available in D programming language −

import std.stdio;

int main(string[] args) { 
   int a = 20; 
   int b = 10; 
   int c = 15; 
   int d = 5; 
   int e;
   
   e = (a + b) * c / d;      // ( 30 * 15 ) / 5 
   writefln("Value of (a + b) * c / d is : %d\n",  e ); 
   
   e = ((a + b) * c) / d;    // (30 * 15 ) / 5 
   writefln("Value of ((a + b) * c) / d is  : %d\n" ,  e );  
   
   e = (a + b) * (c / d);   // (30) * (15/5) 
   writefln("Value of (a + b) * (c / d) is  : %d\n",  e );
   
   e = a + (b * c) / d;     //  20 + (150/5) 
   writefln("Value of a + (b * c) / d is  : %d\n" ,  e ); 
  
   return 0;
}

When you compile and execute the above program, it produces the following result −

Value of (a + b) * c / d is : 90 
 
Value of ((a + b) * c) / d is  : 90
  
Value of (a + b) * (c / d) is  : 90 
 
Value of a + (b * c) / d is  : 50