[development] coding standard question

[Steve Rude]

Very interesting question! Here are the results (look at php5 !?)

slantview:~ steverude$ /Applications/xampp/xamppfiles/bin/php-4.4.7 
test.php
Time for UPPERCASE: 720.796108246 ms

Time for lowercase: 703.890800476 ms

slantview:~ steverude$ /Applications/xampp/xamppfiles/bin/php-5.2.2 
test.php
Time for UPPERCASE: 617.037057877 ms

Time for lowercase: 613.1939888 ms

Just for testing sake, I also changed it to numeric 1 and ran it with == 
instead of === (who uses === most of the time??)

slantview:~ steverude$ /Applications/xampp/xamppfiles/bin/php-4.4.7 
test.php
Failed loading xdebug.so:  (null)
Time for UPPERCASE: 733.495235443 ms

Time for lowercase: 712.421655655 ms

slantview:~ steverude$ /Applications/xampp/xamppfiles/bin/php-5.2.2 
test.php
Failed loading xdebug.so:  (null)
Time for UPPERCASE: 623.962640762 ms

Time for lowercase: 619.996070862 ms


David Strauss wrote:
> What happens if you change the initial "$var = true;" into "$var = TRUE;"?
>
> Steve Rude wrote:
>   
>> I ran this test just to see what would happen, and here are the results,
>> feel free to test it yourself.  According to this test, running a simple
>> loop with one if statement 100k times, you lose about 20ms using
>> uppercase.  What is interesting, is that the same test in php5 runs
>> 100ms faster. 
>>
>> slantview:~ steverude$ /Applications/xampp/xamppfiles/bin/php-4.4.7
>> test.php
>> Time for UPPERCASE: 723.675251007 ms
>>
>> Time for lowercase: 702.354669571 ms
>>
>> slantview:~ steverude$ /Applications/xampp/xamppfiles/bin/php-5.2.2
>> test.php
>> Time for UPPERCASE: 622.086286545 ms
>>
>> Time for lowercase: 607.203245163 ms
>>
>>
>> Another interesting stat is that we have 2383 times in a stock drupal
>> 5.1 distribution where we use an uppercase TRUE, FALSE or NULL.
>>
>> Reference:
>>
>> slantview:~/Documents/workspace/drupal-5.1 steverude$ grep -r TRUE * | wc -l
>>      629
>> slantview:~/Documents/workspace/drupal-5.1 steverude$ grep -r FALSE * |
>> wc -l
>>      511
>> slantview:~/Documents/workspace/drupal-5.1 steverude$ grep -r NULL * | wc -l
>>     1243
>>
>> So it does not seem that unreasonable to me that we could potentially
>> get some performance gain by standardizing on lower case true, false and
>> null.  Preference aside (me being on the uppercase side), I believe that
>> adding this standard to the drupal standards could potentially give us a
>> small amount of performance increase.
>>
>> I also think the issue should be documented in the coding standard and
>> reflected in the Coder module regardless of the decision.
>>
>> Here is the code for the test:
>>
>> slantview:~ steverude$ cat test.php
>> <?php
>>
>> function microtime_float() {
>>   list($usec, $sec) = explode(" ", microtime());
>>   return ((float)$usec + (float)$sec);
>> }
>>
>> $var = true;
>>
>> $time_total = 0;
>> for ($i = 0; $i < 100000; ++$i) {
>>   $time_start = microtime_float();
>>   if ($var === TRUE) {
>>     $time_end = microtime_float();
>>     $time_total += $time_end - $time_start;
>>   }
>> }
>> $time_total = $time_total * 1000;
>> print "Time for UPPERCASE: $time_total ms\n\n";
>>
>> $time_total = 0;
>> for ($i = 0; $i < 100000; ++$i) {
>>   $time_start = microtime_float();
>>   if ($var === true) {
>>     $time_end = microtime_float();
>>     $time_total += $time_end - $time_start;
>>   }
>> }
>> $time_total = $time_total * 1000;
>> print "Time for lowercase: $time_total ms\n\n";
>>
>> Thanks,
>>
>> Steve Rude
>>
>> Karoly Negyesi wrote:
>>     
>>> I do not believe that true could be faster than TRUE when php is case agnostic about its identifiers. Maybe there is time taken to lowercase TRUE ... but if you can measure lowercasing four characters in the parsing stage where only ASCII is supported, congratulations. 
>>>
>>> About commas, yes the D5 menu defintiions are ugly sometimes. Have you seen D6 :) ?
>>>
>>>   
>>>       
>> -- 
>> Steve Rude + Lead Developer
>> *AchieveInternet*
>> (800) 618-877 x 202
>>
>> http://www.achieveinternet.com
>>     
>
>   


-- 
Steve Rude + Lead Developer
*AchieveInternet*
(800) 618-877 x 202

http://www.achieveinternet.com
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