Subtraction Operator; Subtraction Assignment Operator - MACROMEDIA FLASH 8-ACTIONSCRIPT 2.0 LANGUAGE Reference

- 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
When used for subtracting, it performs an arithmetic subtraction on two numerical
expressions, subtracting
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
expression2 : Number
Returns
- An integer or floating-point number.
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
two statements are equivalent:
String expressions must be converted to numbers; otherwise,
Availability: ActionScript 1.0; Flash Player 4
188 ActionScript language elements
from
expression2
- A number or expression that evaluates to a number.
- A number or expression that evaluates to a number.
the value of
expression1- expression2
x -= y ;x = x - y;
. When both expressions are
expression1
NaN
. Usage 2:
expression
. For example, the following
(not a number) is returned.