Expression Statement (C)


When an expression statement is executed, the expression is evaluated according to the rules outlined in Expressions and Assignments.


expression opt ;

All side effects from the expression evaluation are completed before the next statement is executed. An empty expression statement is called a null statement. See The Null Statement for more information.

These examples demonstrate expression statements.

x = ( y + 3 );            /* x is assigned the value of y + 3  */
x++;                      /* x is incremented                  */
x = y = 0;                /* Both x and y are initialized to 0 */
proc( arg1, arg2 );       /* Function call returning void      */
y = z = ( f( x ) + 3 );   /* A function-call expression        */

In the last statement, the function-call expression, the value of the expression, which includes any value returned by the function, is increased by 3 and then assigned to both the variables y and z.