User Guide

188 ActionScript language elements
- subtraction operator
(Negation) -expression
(Subtraction) expression1 - expression2
Used for negating or subtracting.
Usage 1: When used for negating, it reverses the sign of the numerical
expression. Usage 2:
When used for subtracting, it performs an arithmetic subtraction on two numerical
expressions, subtracting
expression2 from expression1. When both expressions are
integers, the difference is an integer. When either or both expressions are floating-point
numbers, the difference is a floating-point number.
Availability: ActionScript 1.0; Flash Player 4
Operands
expression1 : Number - A number or expression that evaluates to a number.
expression2 : Number - A number or expression that evaluates to a number.
Returns
Number - An integer or floating-point number.
Example
Usage 1: The following statement reverses the sign of the expression 2 + 3:
trace(-(2+3)); // output: -5
Usage 2: The following statement subtracts the integer 2 from the integer 5:
trace(5-2); // output: 3
The result, 3, is an integer. Usage 3: The following statement subtracts the floating-point
number 1.5 from the floating-point number 3.25:
trace(3.25-1.5); // output: 1.75
The result, 1.75, is a floating-point number.
-= subtraction assignment operator
expression1 -= expression2
Assigns expression1 the value of expression1- expression2. For example, the following
two statements are equivalent:
x -= y ;x = x - y;
String expressions must be converted to numbers; otherwise, NaN (not a number) is returned.
Availability: ActionScript 1.0; Flash Player 4