[Vtigercrm-developers] A question on efficiency/semantics...

[Alan Lord]

That's helpful info,

So it seems using empty() _is_ actually a good solution. And that 
count() is probably unnecessary in the initial example I gave?

Thanks.

Al


On 06/05/2021 06:17, Mariusz Krzaczkowski | YetiForce Sp. z o.o. wrote:
> Notice: Undefined variable /  Undefined index / Undefined offset
> 
> This is a bug that causes a lot of problems,
> no one knows if it's on purpose or if someone forgot to change something 
> or made a typo.
> 
> https://stackoverflow.com/questions/4261133/notice-undefined-variable-notice-undefined-index-and-notice-undefined#answer-4261200 
> <https://stackoverflow.com/questions/4261133/notice-undefined-variable-notice-undefined-index-and-notice-undefined#answer-4261200>
> 
>  From the vast wisdom of thePHP Manual 
> <http://php.net/manual/en/language.variables.basics.php#example-112>:
> 
>> Relying on the default value of an uninitialized variable is 
>> problematic in the case of including one file into another which uses 
>> the same variable name. It is also a majorsecurity risk 
>> <http://www.php.net/manual/en/security.globals.php>withregister_globals <http://www.php.net/manual/en/ini.core.php#ini.register-globals>turned 
>> on.E_NOTICE 
>> <http://www.php.net/manual/en/errorfunc.constants.php#errorfunc.constants.errorlevels.e-notice>level 
>> error is issued in case of working with uninitialized variables, 
>> however not in the case of appending elements to the uninitialized 
>> array.isset() 
>> <http://www.php.net/manual/en/function.isset.php>language construct 
>> can be used to detect if a variable has been already initialized. 
>> Additionally and more ideal is the solution ofempty() 
>> <http://php.net/manual/en/function.empty.php>since it does not 
>> generate a warning or error message if the variable is not initialized.
>>
> --
> Z poważaniem / Kind regards
> Mariusz Krzaczkowski
> 
> W dniu 2021-05-05 17:36, Alan Lord napisał(a):
> 
>> Interesting.
>>
>> That seems like good/valid Warning - it should encourage the 
>> declaration of variables at the start of each routine.
>>
>> Maybe for a variable variable it might not make sense but those aren't 
>> that common it seems to me?
>>
>> Nice to hear from you Joe. Hope all's well.
>>
>> Cheers
>>
>> Al
>>
>>
>> On 05/05/2021 16:24, Joe Bordes wrote:
>>> Sadly, PHP warning system doesn't work that way:
>>>
>>> ----
>>>
>>> <?php
>>> error_reporting(-1);
>>> ini_set('display_errors', 1);
>>>
>>> if ($nothere) {
>>>      echo "it is here";
>>> } else {
>>>      echo "it isn't here";
>>> }
>>> -----
>>>
>>> result
>>>
>>> -----
>>>
>>> joe at linuxmint:/var/www/coreBOSTest$ php k.php
>>> PHP Notice:  Undefined variable: nothere in 
>>> /var/www/coreBOSTest/k.php on line 5
>>> PHP Stack trace:
>>> PHP   1. {main}() /var/www/coreBOSTest/k.php:0
>>>
>>> Notice: Undefined variable: nothere in /var/www/coreBOSTest/k.php on line 5
>>>
>>> Call Stack:
>>>      0.0001     393600   1. {main}() /var/www/coreBOSTest/k.php:0
>>>
>>> it isn't here
>>>
>>> ------
>>>
>>>
>>> so you get the warning if the variable is not defined which is what 
>>> you are trying to avoid
>>>
>>
>>
>>
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> 
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