Re: foreach and destroying variables for memory saving

Tim | iHostNZ schrieb:
Hi All,

Just to annoy the hell out of you, another thing that has been on my mind
for a while:

I love the foreach ($ar as $k => $v) { ... } construct and use it all the
time. However, I read somewhere that foreach actually uses a copy of $ar
instead of the array itself by reference. Wouldn't it be much more
usefull/efficient, if foreach would use the array by reference? Then one
could change arrays while iterating over them (without having to use the old
fashioned for ($i=0; $i<count($ar); $i++), also this doesnt work for
associative arrays). I know you can do it with while and list somehow, but i
personally find that language construct rather ugly and can never remember
it. Is there another way that any of you use? Please enlighten me.
I just use foreach because its easy, but it might not be the best. However,
it seems to perform good enough for what i've done so far.

Somewhere i also read that one can save a lot of memory by destroying
variables. Is that done with unset, setting it to null or something similar?
So, i take there is no garbage collection in php? I've never actually looked
at the c source code of php. Maybe its time to actually do that. But it
might be easier if someone can answer this from the top of their head.

Thanks for your patience.

Hi Tim,
i can remember me to hear/read that the variables on PHP will be destroy automatically?.

Regards

Carlos
.

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