Don’t unset that variable you need globally

[steve]

Dont’ make my mistake. It is costly.

Say you have defined a variable $var in your main script.

Now in a function you access it using:
global $var;

But you want to set it to null inside the function.
DO: $var = null;
DONT DO: unset($var);

Why? Because the 2nd way removes the variable from the name space,
and it is no longer globally available. Cost me 10 hours....

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[Exyle]

steve wrote:

Dont’ make my mistake. It is costly.

Say you have defined a variable $var in your main script.

Now in a function you access it using:
global $var;

But you want to set it to null inside the function.
DO: $var = null;
DONT DO: unset($var);

Why? Because the 2nd way removes the variable from the name space,
and it is no longer globally available. Cost me 10 hours....

Thanks for the heads up, although I do remember reading something along
these lines in the PHP manual.

[Berislav Lopac]

steve wrote:

Dont’ make my mistake. It is costly.

Say you have defined a variable $var in your main script.

Now in a function you access it using:
global $var;

But you want to set it to null inside the function.
DO: $var = null;
DONT DO: unset($var);

Why? Because the 2nd way removes the variable from the name space,
and it is no longer globally available. Cost me 10 hours....

Even better -- don't use global variables.

Berislav

[steve]

"" wrote:

steve wrote:

Dont’ make my mistake. It is costly.

Say you have defined a variable $var in your main script.

Now in a function you access it using:
global $var;

But you want to set it to null inside the function.
DO: $var = null;
DONT DO: unset($var);

Why? Because the 2nd way removes the variable from the name

space,

and it is no longer globally available. Cost me 10 hours....

Thanks for the heads up, although I do remember reading
something along
these lines in the PHP manual.

You are welcome, and if you find that inf on php site, please post.

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[Kimmo Laine]

"steve" <Us************ @dbForumz.com> wrote in message
news:4_******** *************** *************** *@dbforumz.com. ..

Dont’ make my mistake. It is costly.

Say you have defined a variable $var in your main script.

Now in a function you access it using:
global $var;

But you want to set it to null inside the function.
DO: $var = null;
DONT DO: unset($var);

Why? Because the 2nd way removes the variable from the name space,
and it is no longer globally available. Cost me 10 hours....

That's odd. The manual seems to disagree:

"If a globalized variable is unset() inside of a function, only the local
variable is destroyed. The variable in the calling environment will retain
the same value as before unset() was called.

<?php
function destroy_foo()
{
global $foo;
unset($foo);
}

$foo = 'bar';
destroy_foo();
echo $foo; // prints "bar"
?>"
- from http://fi.php.net/manual/en/function.unset.php

Now I don't know what to believe..

--
Welcome to Usenet! Please leave tolerance, understanding
and intelligence at the door. They aren't welcome here.
eternal piste erection miuku gmail piste com

[Hilarion]

> Steve wrote:

Say you have defined a variable $var in your main script.

Now in a function you access it using:
global $var;

But you want to set it to null inside the function.
DO: $var = null;
DONT DO: unset($var);

Why? Because the 2nd way removes the variable from the name space,
and it is no longer globally available. Cost me 10 hours....

Kimmo Laine wrote: That's odd. The manual seems to disagree:

"If a globalized variable is unset() inside of a function, only the local
variable is destroyed. The variable in the calling environment will retain
the same value as before unset() was called.

<?php
function destroy_foo()
{
global $foo;
unset($foo);
}

$foo = 'bar';
destroy_foo();
echo $foo; // prints "bar"
?>"
- from http://fi.php.net/manual/en/function.unset.php

That's exactly what Steve said. He said that the variable is removed
from current namespace (function namespace), not that it's totaly
removed.

"global" keyword is like setting local reference to global variable.
When you call "unset", then you unset reference to that variable.
To "unset" global variable from a function you'll have to
"unset( $_GLOBAL['foo'] )".
Hilarion

[Hilarion]

> > steve wrote:

Say you have defined a variable $var in your main script.

Now in a function you access it using:
global $var;

But you want to set it to null inside the function.
DO: $var = null;
DONT DO: unset($var);

Why? Because the 2nd way removes the variable from the name
space,
and it is no longer globally available. Cost me 10 hours....

[...] if you find that inf on php site, please post.

Read Kimmo Laine post. It contains the link and manual fragment
which describes the case ("the local variable is destroyed").

Hilarion

[Kimmo Laine]

"Hilarion" <hi******@SPAM. op.SMIECI.pl> wrote in message
news:da******** **@news.onet.pl ...

Steve wrote:

> Say you have defined a variable $var in your main script.
>
> Now in a function you access it using:
> global $var;
>
> But you want to set it to null inside the function.
> DO: $var = null;
> DONT DO: unset($var);
>
> Why? Because the 2nd way removes the variable from the name space,
> and it is no longer globally available. Cost me 10 hours....

Kimmo Laine wrote:

That's odd. The manual seems to disagree:

"If a globalized variable is unset() inside of a function, only the local
variable is destroyed. The variable in the calling environment will
retain the same value as before unset() was called.

<?php
function destroy_foo()
{
global $foo;
unset($foo);
}

$foo = 'bar';
destroy_foo();
echo $foo; // prints "bar"
?>"
- from http://fi.php.net/manual/en/function.unset.php

That's exactly what Steve said. He said that the variable is removed
from current namespace (function namespace), not that it's totaly
removed.

I somehow thought he meant from the entire namespace, not from current...
Okay, my bad. Now it all makes sense.

--
Welcome to Usenet! Please leave tolerance, understanding
and intelligence at the door. They aren't welcome here.
eternal piste erection miuku gmail piste com

[steve]

"Kimmo Laine" <et************ ******@Mgmail.c om> wrote in message
news:DV******** *********@reade r1.news.jippii. net...
| "Hilarion" <hi******@SPAM. op.SMIECI.pl> wrote in message
| news:da******** **@news.onet.pl ...
| >> Steve wrote:
| >> > Say you have defined a variable $var in your main script.
| >> >
| >> > Now in a function you access it using:
| >> > global $var;
| >> >
| >> > But you want to set it to null inside the function.
| >> > DO: $var = null;
| >> > DONT DO: unset($var);
| >> >
| >> > Why? Because the 2nd way removes the variable from the name space,
| >> > and it is no longer globally available. Cost me 10 hours....
| >
| > Kimmo Laine wrote:
| >> That's odd. The manual seems to disagree:
| >>
| >> "If a globalized variable is unset() inside of a function, only the
local
| >> variable is destroyed. The variable in the calling environment will
| >> retain the same value as before unset() was called.
| >>
| >> <?php
| >> function destroy_foo()
| >> {
| >> global $foo;
| >> unset($foo);
| >> }
| >>
| >> $foo = 'bar';
| >> destroy_foo();
| >> echo $foo; // prints "bar"
| >> ?>"
| >> - from http://fi.php.net/manual/en/function.unset.php
| >
| > That's exactly what Steve said. He said that the variable is removed
| > from current namespace (function namespace), not that it's totaly
| > removed.
|
|
| I somehow thought he meant from the entire namespace, not from current...
| Okay, my bad. Now it all makes sense.

hmmm...i don't believe you have mis-read anything. i read steve's op that
same way you did *and* the problem he describes *does* conflict with the php
manual. but then again, we may both be having problems with our reading
comprehension. ;^)

[Hilarion]

> hmmm...i don't believe you have mis-read anything. i read steve's op that

same way you did *and* the problem he describes *does* conflict with the php
manual. but then again, we may both be having problems with our reading
comprehension. ;^)

:)

OK. The way I read it was:
Say you have defined a variable $var in your main script.

Now in a function you access it using:
global $var;
I suppose the above text was clear and requires no translation.

But you want to set it to null inside the function.
The above means "you want to unset global variable $var / set it
to null"

DO: $var = null;
DONT DO: unset($var);

Why? Because the 2nd way removes the variable from the name space,
"Because the 2nd way removes the variable from current (function) namespace"

and it is no longer globally available.
"You do not have acces to the global variable from current (function) scope."

Cost me 10 hours....

Hilarion

PS.: The fact that English is not my native language is probably influencing
the way that I read it.