foreach with null

+1 as well if and only if this applies to IS_NULL

I'd say silently ignoring it and moving along is fine here.
Only if the var IS_NULL, but this is the case.

So I'm +1.

Hello internals,

i would like to change foreach a tiny bit. Actually i don't like the
warning when using foreach with null.

marcus@zaphod /usr/src/php-cvs $ php -r '$n=NULL; foreach($n as $v);'
make: `sapi/cli/php' is up to date.

Warning: Invalid argument supplied for foreach() in Command line code on line 1
marcus@zaphod /usr/src/php-cvs $ php -r 'foreach(NULL as $v);'
make: `sapi/cli/php' is up to date.

Warning: Invalid argument supplied for foreach() in Command line code on line 1

The way we use NULL in PHP should result in no warning here. The patch for
this can be found here:
http://php.net/~helly/php/ext/ze2/ze2-foreach-null-20051025.diff.txt
It was made with head but applies to 5.1 as well.

Any opinions?

--
Wbr,
Antony Dovgal

It currently is equal:
$ php -r 'var_dump(null == array()); var_dump((array) null);'
bool(true)
array(0) {
}

Ants

Jani Taskinen wrote:

Will the patch make it silently ignore also empty string and 0?
If not, -1. (what's with null being suddenly equal to empty array? :)

--Jani

Hello internals,

i would like to change foreach a tiny bit. Actually i don't like the
warning when using foreach with null.

marcus@zaphod /usr/src/php-cvs $ php -r '$n=NULL; foreach($n as $v);'
make: `sapi/cli/php' is up to date.

Warning: Invalid argument supplied for foreach() in Command line code
on line 1
marcus@zaphod /usr/src/php-cvs $ php -r 'foreach(NULL as $v);'
make: `sapi/cli/php' is up to date.

Warning: Invalid argument supplied for foreach() in Command line code
on line 1

The way we use NULL in PHP should result in no warning here. The patch
for
this can be found here:
http://php.net/~helly/php/ext/ze2/ze2-foreach-null-20051025.diff.txt
It was made with head but applies to 5.1 as well.

Any opinions?

Best regards,
Marcus

Ilia Alshanetsky wrote:

IMHO this is a bad idea, if you really wanted to support NULL in a
particular case you, as a developer could do:
php -r '$n=NULL; foreach((array)$n as $v);'

Making NULL usage transparent where array is expects will lead to
difficult to debug code.

hi :-)

the warning for foreach() in this case seems to be inconsistent with:

php -r '$a = null; $b = array(); var_dump((empty($a) === empty($b)), (count($a) === count($b)));'

which gives no warnings or otherwise, also as a lesser developer than you I don't
buy the notion that dropping the warning makes debugging more difficult because
advanced code should be checking vars properly before using them and, well,
for any given foreach loop there is often enough an 'if (!count($array))'-like
statement to take care of the 'empty' case. and in cases when speed is very important
it saves an explicit cast (is that more expensive anyway?) and it means not requiring
an '@' to suppress which I do know is more expensive than not having any E_* to suppress at all.

on the face of it I understand begin against, feedback is good.
but removing the warning would make the engine behaviour just a little
more consistent - which is nice, no?

function(MyCLass $x = null) {}

which was nice from the start fom a user perspective,
I was puzzled as to why it went, glad it came back and
hope it says :-)
</sidenote>

thanks for php, and kind regards in general,
jochem

-1 for removing the warning.

Ilia

IMHO this is a bad idea, if you really wanted to support NULL in a
particular case you, as a developer could do:
php -r '$n=NULL; foreach((array)$n as $v);'

Making NULL usage transparent where array is expects will lead to
difficult to debug code.

-1 for removing the warning.

Yes, I agree, we should not remove this warning.

Derick

--
Derick Rethans
http://derickrethans.nl | http://ez.no | http://xdebug.org