[Laszlo-dev] UPDATED For Review: Change 20090105-hqm-R Summary: fix url encoding problem

André Bargull andre.bargull at udo.edu
Tue Jan 6 09:30:43 PST 2009


Even with a constant table, it's still about 48 times slower on my 
machine. And Tucker's quote doesn't imply you shouldn't take an obvious, 
more effective alternative.


On 1/6/2009 6:13 PM, Henry Minsky wrote:
> That is a good question.  I really take Tucker's quotation to heart though,
> 
> Rules of Optimization:
>  Rule 1: Don't do it.
>  Rule 2 (for experts only): Don't do it yet.
>  — M.A. Jackson
> "More computing sins are committed in the name of efficiency (without
> necessarily
> achieving it) than for any other single reason - including blind stupidity."
>  — W.A. Wulf
> "We should forget about small efficiencies, say about 97% of the time: premature
> optimization is the root of all evil."
>  — Donald Knuth
> "The best is the enemy of the good."
>  — Voltaire
> 
> 
> Even if it is slow, it doesn't seem like a typical application would spend
> that much absolute time encoding data. If it is a noticable
> performance issue, I  bet we could
> speed it up a lot with  a lookup table hex[value]
> to encode the two digit sequences instead of a function call to
> value.toString().toUpperCase().
> 
> 
>    var hex = {
>     "%00", "%01", "%02", "%03", "%04", "%05", "%06", "%07",
>     "%08", "%09", "%0a", "%0b", "%0c", "%0d", "%0e", "%0f",
>     "%10", "%11", "%12", "%13", "%14", "%15", "%16", "%17",
>     "%18", "%19", "%1a", "%1b", "%1c", "%1d", "%1e", "%1f",
>     "%20", "%21", "%22", "%23", "%24", "%25", "%26", "%27",
>     "%28", "%29", "%2a", "%2b", "%2c", "%2d", "%2e", "%2f",
>     "%30", "%31", "%32", "%33", "%34", "%35", "%36", "%37",
>     "%38", "%39", "%3a", "%3b", "%3c", "%3d", "%3e", "%3f",
>     "%40", "%41", "%42", "%43", "%44", "%45", "%46", "%47",
>     "%48", "%49", "%4a", "%4b", "%4c", "%4d", "%4e", "%4f",
>     "%50", "%51", "%52", "%53", "%54", "%55", "%56", "%57",
>     "%58", "%59", "%5a", "%5b", "%5c", "%5d", "%5e", "%5f",
>     "%60", "%61", "%62", "%63", "%64", "%65", "%66", "%67",
>     "%68", "%69", "%6a", "%6b", "%6c", "%6d", "%6e", "%6f",
>     "%70", "%71", "%72", "%73", "%74", "%75", "%76", "%77",
>     "%78", "%79", "%7a", "%7b", "%7c", "%7d", "%7e", "%7f",
>     "%80", "%81", "%82", "%83", "%84", "%85", "%86", "%87",
>     "%88", "%89", "%8a", "%8b", "%8c", "%8d", "%8e", "%8f",
>     "%90", "%91", "%92", "%93", "%94", "%95", "%96", "%97",
>     "%98", "%99", "%9a", "%9b", "%9c", "%9d", "%9e", "%9f",
>     "%a0", "%a1", "%a2", "%a3", "%a4", "%a5", "%a6", "%a7",
>     "%a8", "%a9", "%aa", "%ab", "%ac", "%ad", "%ae", "%af",
>     "%b0", "%b1", "%b2", "%b3", "%b4", "%b5", "%b6", "%b7",
>     "%b8", "%b9", "%ba", "%bb", "%bc", "%bd", "%be", "%bf",
>     "%c0", "%c1", "%c2", "%c3", "%c4", "%c5", "%c6", "%c7",
>     "%c8", "%c9", "%ca", "%cb", "%cc", "%cd", "%ce", "%cf",
>     "%d0", "%d1", "%d2", "%d3", "%d4", "%d5", "%d6", "%d7",
>     "%d8", "%d9", "%da", "%db", "%dc", "%dd", "%de", "%df",
>     "%e0", "%e1", "%e2", "%e3", "%e4", "%e5", "%e6", "%e7",
>     "%e8", "%e9", "%ea", "%eb", "%ec", "%ed", "%ee", "%ef",
>     "%f0", "%f1", "%f2", "%f3", "%f4", "%f5", "%f6", "%f7",
>     "%f8", "%f9", "%fa", "%fb", "%fc", "%fd", "%fe", "%ff"
>   };
> 
> 
> 
> 
> On Tue, Jan 6, 2009 at 12:07 PM, André Bargull <andre.bargull at udo.edu> wrote:
>>
>> On 1/6/2009 5:49 PM, Henry Minsky wrote:
>>> I like having a single common url escape routine across all runtimes,
>>> it makes debugging simpler.
>> Even if it is _much_ slower? The following testcase (in swf8) was about 50
>> times slower when "escape_utf8" was used instead of "escape"...
>>
>>
>> ---
>> <canvas bgcolor="0x898989" debug="true">
>>  <button text="escape" >
>>    <handler name="onclick" ><![CDATA[
>>      var d = new Date();
>>      for (var i=0; i<4000; ++i)escape("encode me éêè");
>>      Debug.write(new Date()-d)
>>    ]]></handler>
>>  </button>
>>
>>  <button x="100" text="escape_utf8" >
>>    <handler name="onclick" ><![CDATA[
>>      function escape_utf8 (s) {
>>        var utf8 = "";
>>        for (var i = 0, len = s.length; i < len; ++i) {
>>          var c = s.charCodeAt(i);
>>          if ((c >= 0x30 && c <= 0x39) // 0-9
>>              || (c >= 0x41 && c <= 0x5A) // A-Z
>>              || (c >= 0x61 && c <= 0x7A)) {// a-z
>>              utf8 += s.charAt(i);
>>          } else if (c <= 0x7F) {
>>              // 0xxxxxxx
>>              utf8 += "%" + (c).toString(16).toUpperCase();
>>          } else if (c <= 0x7FF) {
>>              // 110xxxxx 10xxxxxx
>>              utf8 += "%" + ((c >> 6) | 0xC0).toString(16).toUpperCase();
>>              utf8 += "%" + ((c & 0x3F) | 0x80).toString(16).toUpperCase();
>>          } else if (c <= 0xFFFF) {
>>              // 1110xxxx 10xxxxxx 10xxxxxx
>>              utf8 += "%" + ((c >> 12) | 0xE0).toString(16).toUpperCase();
>>              utf8 += "%" + (((c >> 6) & 0x3F) |
>> 0x80).toString(16).toUpperCase();
>>              utf8 += "%" + ((c & 0x3F) | 0x80).toString(16).toUpperCase();
>>          } else {
>>              // 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
>>              utf8 += "%" + ((c >> 18) | 0xF0).toString(16).toUpperCase();
>>              utf8 += "%" + (((c >> 12) & 0x3F) |
>> 0x80).toString(16).toUpperCase();
>>              utf8 += "%" + (((c >> 6) & 0x3F) |
>> 0x80).toString(16).toUpperCase();
>>              utf8 += "%" + ((c & 0x3F) | 0x80).toString(16).toUpperCase();
>>          }
>>        }
>>        return utf8;
>>      }
>>
>>      var d = new Date();
>>      for (var i=0; i<4000; ++i)escape_utf8("encode me éêè")
>>      Debug.write(new Date()-d)
>>    ]]></handler>
>>  </button>
>> </canvas>
>> ---
>>
>>
>>
>>> I just modified your utf8 escape routine to pad the extra zero when needed
>>>
>>>
>>> var escape_utf8 = function (s:String):String {
>>>  var utf8 = "";
>>>  for (var i = 0, len = s.length; i < len; ++i) {
>>>    var c = s.charCodeAt(i);
>>>    if ((c >= 0x30 && c <= 0x39) // 0-9
>>>        || (c >= 0x41 && c <= 0x5A) // A-Z
>>>        || (c >= 0x61 && c <= 0x7A)) {// a-z
>>>      utf8 += s.charAt(i);
>>>    } else if (c < 0x10) {
>>>      // 0xxxxxxx
>>>      utf8 += "%0" + (c).toString(16).toUpperCase();
>>>    } else if (c <= 0x7F) {
>>>      // 0xxxxxxx
>>>      utf8 += "%" + (c).toString(16).toUpperCase();
>>> ...
>>> ...
>>>
>>>
>>>
>>>
>>> On Tue, Jan 6, 2009 at 11:49 AM, André Bargull <andre.bargull at udo.edu>
>>> wrote:
>>>> As an alternative, we could (maybe should?) use:
>>>> - in swf8: escape
>>>> - in dhtml+swf9: encodeURIComponent [1] with a few modifications so it
>>>> also
>>>> encodes "- _ . ! ~ * ' ( )" into the appropriate UTF-8 encoding
>>>>
>>>> [1]
>>>>
>>>> "https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Global_Functions/encodeURIComponent"
>>>>
>>>>
>>>>
>>>> On 1/6/2009 5:29 PM, Henry Minsky wrote:
>>>>> Hang on, there's a bug in the escape_utf8 routine, it's encoding
>>>>> newline as "%A" instead of "%0A", I need
>>>>> to fix that.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> On Tue, Jan 6, 2009 at 2:19 AM, Henry Minsky <henry.minsky at gmail.com>
>>>>> wrote:
>>>>>> Change 20090105-hqm-R by hqm at badtzmaru.home on 2009-01-05 19:40:54 EST
>>>>>>  in /Users/hqm/openlaszlo/trunk3/WEB-INF/lps/lfc
>>>>>>  for http://svn.openlaszlo.org/openlaszlo/trunk/WEB-INF/lps/lfc
>>>>>>
>>>>>> Summary: fix url encoding problem
>>>>>>
>>>>>> New Features:
>>>>>>
>>>>>> Bugs Fixed: LPP-7532
>>>>>>
>>>>>> Technical Reviewer: andre
>>>>>> QA Reviewer: ptw
>>>>>> Doc Reviewer: (pending)
>>>>>>
>>>>>> Documentation:
>>>>>>
>>>>>> Release Notes:
>>>>>>
>>>>>> The recommended way to url-escape strings is to call
>>>>>> lz.Browser.urlEscape.
>>>>>> This works similar to the Javascript encodeURIComponent function, but
>>>>>> is
>>>>>> preferable
>>>>>> because there are some knows bugs with encodeURIComponent on some
>>>>>> platforms.
>>>>>>
>>>>>> Details:
>>>>>>
>>>>>> Use Andre's utf-8 clean implementation of encodeURIComponent.
>>>>>>
>>>>>> Tests:
>>>>>>
>>>>>> demos/amazon/amazon.lzx in swf8,swf9,dhtml
>>>>>> test/lfc/data/alldata.lzx (alldata.lzx has bugs, but there should be no
>>>>>> regressions from behavior in trunk)
>>>>>> demos/lzpix/app.lzx in swf8,swf9,dhtml
>>>>>> demos/calendar/calendar.lzx in swf8,swf9,dhtml
>>>>>>
>>>>>> Files:
>>>>>> M      kernel/swf/LzLoadQueue.as
>>>>>> M      services/LzBrowser.lzs
>>>>>> M      debugger/platform/swf9/LzFlashRemote.as
>>>>>> M      data/LzParam.lzs
>>>>>> M      compiler/LzRuntime.lzs
>>>>>> M      compiler/LzBootstrapDebugService.lzs
>>>>>>
>>>>>> Changeset:
>>>>>> http://svn.openlaszlo.org/openlaszlo/patches/20090105-hqm-R.tar
>>>>>>
>>>>>
>>>
>>>
>>
> 
> 
> 



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