|
|
Posted by ColdShine on 03/13/06 03:22
Anonymous in news:441326E4.66903A5B@nowhere.invalid wrote:
> ColdShine wrote:
>
>> There's no clear example stating this, but:
>>
>> echo "$array[key]";
>>
>> Is EXACTLY the same as:
>>
>> echo "{$array['key']}";
>
> No, Jerry is right, they are not the same.
>
> $array[key] is an array with a constant called key as index,
> $array['key'] is an array with the string 'key' as index.
Please read my post twice. I'm not talking about using $arr[key], but I'm
talking 'bout using "$arr[key]". If you can't understand the difference, you
should not be correcting me.
> You will see the difference as soon as you assign a value to the
> constant key. :-)
No way. The constant called key is ONLY used when referring to $arr[key]
from OUTSIDE a doublequote'd string, or when using curly syntax.
> When using $array[key] PHP will try to find the constant key, but
> intelligently will assume you actually meant 'key' when it figures out
> that the constant is undefined. Here is the error from the log:
>
> [Sat Mar 11 19:29:40 2006] [error] [client 127.0.0.1] PHP Notice: Use
> of undefined constant key - assumed 'key' in C:\\webroot\\test.php on
> line 4
>
> The PHP manual says on this topic:
>
>
> Note: Enabling E_NOTICE during development has some benefits. For
> debugging purposes: NOTICE messages will warn you about possible bugs in
> your code. For example, use of unassigned values is warned. It is
> extremely useful to find typos and to save time for debugging. NOTICE
> messages will warn you about bad style. For example, $arr[item] is
> better to be written as $arr['item'] since PHP tries to treat "item" as
> constant. If it is not a constant, PHP assumes it is a string index for
> the array.
Both you and the PHP manual are STILL talking about $arr[item] being used
OUTSIDE a complex (doublequote'd) string (or again, with curly syntax).
> However, strangely enough this warning showed up in the log only the
> first time I accessed the page! No more warnings on any subsequent
> accesses to the page or any other page with that kind of error!
>
> I just checked the config, ignore_repeated_errors and
> ignore_repeated_source are set to off. I also confirmed these settings
> with phpinfo(). However, PHP reacts as if both are set to on! Did I just
> find a bug?
>
> That would explain why you get no warnings! You probably got your first
> and only warning a long time ago if you always program like that. ;-)
If you write $arr[key] you get an E_NOTICE unless there's a constant named
'key'.
If you write "$arr[key]" you get an E_NOTICE unless 'key' is a defined index
in $arr.
I don't think there's anything complex to understand here. And no, I didn't
turn on such an idiot-friendly option as ignoring
warnings/errors/whatsoever.
Here's a quick roundup, if you (or anyone f'wing this thread) still are
wondering WHAT is meant WHEN:
<?php
$arr = array('key' => 'foo');
define('key', 'another');
echo $arr[key]; // undefined index ('another')
echo $arr['key']; // foo
echo '$arr[key]'; // $arr[key]
echo "$arr[key]"; // foo
echo "$arr['key']"; // parse error
echo "{$arr[key]}"; // undefined index ('another')
echo "{$arr['key']}"; // foo
?>
This should rule out any misunderstandings.
Btw,
<?php
$arr = array('c' => 'Cheers', 'f' => 'F**k off');
define('c', 'f');
echo "$arr[c] :-)";
?>
--
ColdShine
"Experience is a hard teacher: she gives the test first, the lesson
afterwards." - Vernon Sanders law
Navigation:
[Reply to this message]
|