MACROMEDIA FLASH 8-ACTIONSCRIPT 2.0 LANGUAGE, Reference

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Operators 147
The following example shows the result of the previous example:
var x:Number = 255;
This is because 65535 decimal equals 1111111111111111 binary (sixteen 1s),
1111111111111111 binary shifted right by 8 bits is 11111111 binary, and 11111111 binary
is 255 decimal. The most significant bit is 0 because the integers are 32-bit, so the fill bit is 0.
The following example converts -1 to a 32-bit integer and shifts it 1 bit to the right:
var x:Number = -1 >> 1;
trace(x); // outputs -1
The following example shows the result of the previous example:
var x:Number = -1;
This is because -1 decimal equals 11111111111111111111111111111111 binary (thirty-two
1s), shifting right by one bit causes the least significant (bit farthest to the right) to be
discarded and the most significant bit to be filled in with 1. The result is
11111111111111111111111111111111 (thirty-two 1s) binary, which represents the 32-bit
integer -1.
See also
>>= bitwise right shift and assignment operator
>>= bitwise right shift and assignment operator
expression1 >>= expression2
This operator performs a bitwise right-shift operation and stores the contents as a result in
expression1
.
The following two statements are equivalent:
A >>= B;
A = (A >> B);
Availability: ActionScript 1.0; Flash Player 5
Operands
expression1 : Number
- A number or expression to be shifted right.
expression2 : Number
- A number or expression that converts to an integer from 0 to 31.
Returns
Number
- The result of the bitwise operation.