Can anyone spot the bug?

Paul Derbyshire (ao950@FreeNet.Carleton.CA)
11 Apr 1996 06:49:20 GMT


To: culist-www-html@cunews.carleton.ca
From: ao950@FreeNet.Carleton.CA (Paul Derbyshire)
Subject: Can anyone spot the bug?
Date: 11 Apr 1996 06:49:20 GMT
Message-Id: <4kia1g$m4b@freenet-news.carleton.ca>


This code doesn't work. It The document.clear method should be erasing the
screen but instead of getting each number replacing the previous, the
numbers appear below the previous, like:
10
9
8
7
6
5
4
3
2
1

        function sleep(duration) {
          startTime=new Date()
          var msToWait=1000*duration
          endTime=startTime.getTime()+msToWait
          newTime=new Date()
          var nt1=newTime.getTime()
          while (nt1<endTime) {
            newTime=new Date()
            nt1=newTime.getTime()
          }
        }
        
        function Countdown() {
          prefix="<center><h1>"
          suffix="</h1></center>
          for (var i=10; i>0; i--) {
            document.open()
            document.clear()
            document.close()
            document.open()
            document.write(prefix + i + suffix)
            document.close()
            sleep(1)
          }
        }

I also tried this, using a text box in a form:

        function Countdown() {
          document.open ("text/html")
          document.write("<form name=cntdn action=surpr2.html
method=get>Launch in<input type=text maxlength=2 name=cdtxt> seconds.</form>")
          document.close()
          for (var i=10; i>0; i--) {
            document.open()
            document.cntdn.cdtxt.value=i
            document.close()
            sleep(1)
          }
        }

but it performs even worse. I get "Launch in" and nothing else while it
counts down the ten seconds even though the document.close should ensure
it redraws. When it finishes I see the text box with "1" in it and the
"seconds." Then Netscape crashes with an "invalid page fault".
I can't see anything wrong with these...have I found bugs in Netscape or
something?
--
    .*.  "Clouds are not spheres, mountains are not cones, coastlines are not
 -()  <  circles, and bark is not smooth, nor does lightning travel in a
    `*'  straight line."    ,------------------------------------------------
         -- B. Mandelbrot  |  Paul Derbyshire (PGD) ao950@freenet.carleton.ca