Symbols > -= (subtraction assignment) |  |

-= (subtraction assignment)

subtraction assignment, -=, negation

Availability

Flash Player 4.

Usage

    expression1 -= expression2

Parameters

`expression1,expression2` A number or expression that evaluates to a number.

Returns

Nothing.

Description

Operator (arithmetic compound assignment); assigns `expression1` the value of `expression1` `-` `expression2`. For example, the following two statements are the same:

    x -= y;
    x = x - y;

String expressions must be converted to numbers or `NaN` is returned.

Example

The following example uses the `-=` operator to subtract 10 from 5 and assign the result to the variable `x`.

    x = 5;
    y = 10;
    x -= y
    trace(x);
    //returns -5

Example

The following example shows how strings are converted to numbers.

    x = "5";
    y = "10";
    x -= y;
    trace(x);
    // returns -5