a question about code speed of flex

>What exactly are you demonstrating?  What I see is that evaluating one >compound expression instead of two simpler expressions is about 12 >times slower.  Of course, the actual delta is measured in fractional >microseconds, so it's most likely due to slight variations in your CPU >load at the time of the test, or perhaps the AS VM performing >optimizations part way through the first loop.  Did you try the tests >in reverse order?  In any case, the difference is WAY too small to >care about in pretty much every situation. > >cheers, >barneyb > > >> I think the difference is very big. It seems AS VM optimization is too bad in the body of a for loop. Here is another test, more simple. static function test(text:TextArea):void{            var loop:int = 0;         var i:int = 0;         var j:int = 0;         var k:int = 0;         var now:Date = new Date();         var d:int = 1;         for(i=0;i<10;i++){           for(j=0;j<10000000;j++){           d=1;   //Comment out this  to see difference                    }           now = new Date();                      text.text+=(""+now.getTime()+" "+d+"\n");         }       } If d=1 is executed it cost 10seconds ,if it not execuetd it cost 1 seconds. Can you try to repeat it on your machine,may be I use some wrong complier options.