++ (increment)
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SWiSH Player Support
SWF4 or later - Supported Internally

Syntax
++expression
expression++

Arguments
expression can be a variable, number, element in an array, or the property of an Object.

Returns
++expression returns expression + 1.
expression++ returns expression.


Description
Operator (arithmetic); a pre-increment and post-increment unary operator that adds 1 to expression. The expression can be a variable, element in an array, or property of an Object. The pre-increment form of the operator (++expression) adds 1 to expression and returns the result. The post-increment form of the operator (expression++) adds 1 to expression and returns the initial value of expression (the value prior to the addition).
The pre-increment form of the operator increments x to 2 (x + 1 = 2), and returns the result as y:
x = 1
;
y = ++x
//y is equal to 2, x is equal to 2


The post-increment form of the operator increments x to 2 (x + 1 = 2), and returns the original value of x as the result y:
x = 1;
y = x++;
//y is equal to 1, x is equal to 2


Sample
The following example uses ++ as a post-increment operator to make a while loop run five times.
i = 0;
while(i++ < 5
){
trace("this is execution " + i);
}


This example uses ++ as a pre-increment operator.
var a = [];
var i = 0
;
while (i < 10
{
    a.push(++i);
}

trace(a.join()); // displays "1,2,3,4,5,6,7,8,9,10" in the 'Debug' window


The following example uses ++ as a post-increment operator.
var a = [];
var i = 0
;
while (i < 10
{
a.push(i++);
   }

trace(a.join()); // displays "0,1,2,3,4,5,6,7,8,9" in the 'Debug' window.