MACROMEDIA FLASH 8-ACTIONSCRIPT 2.0 LANGUAGE, Справочник

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146 ActionScript language elements
>> bitwise right shift operator
expression1 >> expression2
Converts
expression1
and
expression2
to 32-bit integers, and shifts all the bits in
expression1
to the right by the number of places specified by the integer that results from
the conversion of
expression2
. Bits that are shifted off the right end are discarded. To
preserve the sign of the original
expression
, the bits on the left are filled in with 0 if the
most significant bit (the bit farthest to the left) of
expression1
is 0, and filled in with 1 if the
most significant bit is 1. Shifting a value right by one position is the equivalent of dividing by
2 and discarding the remainder.
Floating-point numbers are converted to integers by discarding any digits after the decimal
point. Positive integers are converted to an unsigned hexadecimal value with a maximum
value of 4294967295 or 0xFFFFFFFF; values larger than the maximum have their most
significant digits discarded when they are converted so the value is still 32-bit. Negative
numbers are converted to an unsigned hexadecimal value via the two's complement notation,
with the minimum being -2147483648 or 0x800000000; numbers less than the minimum
are converted to two's complement with greater precision and also have the most significant
digits discarded.
The return value is interpreted as a two's complement number with sign, so the return value
will be an integer in the range -2147483648 to 2147483647.
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.
Example
The following example converts 65535 to a 32-bit integer and shifts it 8 bits to the right:
var x:Number = 65535 >> 8;
trace(x); // outputs 255