Can't use function return value in write context--huh?

[kurt.krueckeberg@gmail.com]

Can someone explain why this line
$bool = isset($_POST['email']) && !empty(trim($_P OST['email']));
causes the error message "Can't use function return value in write
context". trim() returns a string. I test if it is empty. So what is
wrong with that?

[Olaf Schinkel]

Re: Can't use function return value in write context--huh?

kurt.krueckeber g@gmail.com schrieb:

Can someone explain why this line
$bool = isset($_POST['email']) && !empty(trim($_P OST['email']));
causes the error message "Can't use function return value in write
context". trim() returns a string. I test if it is empty. So what is
wrong with that?

The functions empty() *only* tests Variables.
All other wil cause an error.

[The Hajj]

Re: Can't use function return value in write context--huh?

On Jul 25, 1:39 pm, kurt.krueckeb.. .@gmail.com wrote:

Can someone explain why this line
$bool = isset($_POST['email']) && !empty(trim($_P OST['email']));
causes the error message "Can't use function return value in write
context". trim() returns a string. I test if it is empty. So what is
wrong with that?

not that speed matters but && $_POST['email'] != '' is how I would do
it.

As mentioned above and to quote from php.net "Note: empty() only
checks variables as anything else will result in a parse error. In
other words, the following will not work: empty(trim($nam e)). "

What I said above is faster than

$email = trim($_POST['email'];

if (... && !empty($email)

[larry@portcommodore.com]

Re: Can't use function return value in write context--huh?

On Jul 25, 10:39 am, kurt.krueckeb.. .@gmail.com wrote:

Can someone explain why this line
$bool = isset($_POST['email']) && !empty(trim($_P OST['email']));
causes the error message "Can't use function return value in write
context". trim() returns a string. I test if it is empty. So what is
wrong with that?)

Your function would fail if 'email' isn't set.

try this:

$bool = !empty( ( isset( $_POST['eamil'] ) ? trim( $_POST['email'] ) :
'' ) );

[Jerry Stuckle]

Re: Can't use function return value in write context--huh?

larry@portcommo dore.com wrote:

On Jul 25, 10:39 am, kurt.krueckeb.. .@gmail.com wrote:

>Can someone explain why this line
>$bool = isset($_POST['email']) && !empty(trim($_P OST['email']));
>causes the error message "Can't use function return value in write
>context". trim() returns a string. I test if it is empty. So what is
>wrong with that?)

>
Your function would fail if 'email' isn't set.
>
try this:
>
$bool = !empty( ( isset( $_POST['eamil'] ) ? trim( $_POST['email'] ) :
'' ) );
>

Incorrect. That's what isset() tests. If $_POST['email'] is not set,
the rest of the expression is never evaluated.

The others had it correct - empty() only works on variables, not the
results of an expression.

--
=============== ===
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attgl obal.net
=============== ===

[kkruecke]

Re: Can't use function return value in write context--huh?

Incorrect. That's what isset() tests. If $_POST['email'] is not set,
the rest of the expression is never evaluated.
>
The others had it correct - empty() only works on variables, not the
results of an expression.

Thanks for mentioning that "If $_POST['email'] is not set, the rest of
the expression is never evaluated." That is why I did
isset( $_POST['eamil']) first.

[Jerry Stuckle]

Re: Can't use function return value in write context--huh?

kkruecke wrote:

>Incorrect. That's what isset() tests. If $_POST['email'] is not set,
>the rest of the expression is never evaluated.
>>
>The others had it correct - empty() only works on variables, not the
>results of an expression.

>
Thanks for mentioning that "If $_POST['email'] is not set, the rest of
the expression is never evaluated." That is why I did
isset( $_POST['eamil']) first.
>

Yep, and that is the correct way to do it.

--
=============== ===
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attgl obal.net
=============== ===