Posted by J.O. Aho on 04/15/07 05:04

Vince Morgan wrote:
> I'm new to php and often discover that what looks like an error to me in a
> piece of code is in fact functionality that I was unaware of.
> In another php forum today I came across the snip below.
> I don't think it's appropriate to ask in that forum while the OP's question
> had not yet been addressed.
> The usage of the curly brackets is screwing with my head, most especialy the
> last line.
>
> foreach (array($section, 'newImage', "${section}_width", "$
> {section}_height") as $val)
> $this->$val =& ${$val};

It's mainly used to tell what is a variable in a string, say you have a
variable called $hell and you have the following

echo "$hellohm's";

this would try to use the variable $hellohm, which most likely would be an
empty variable and result in a string: 's

echo "{$hell}ohm's";

this would use the value of $hell and add ohm's after the value.

The brackets works outside string too, even if it's not that nice looking IMHO.

In the last line ${$val} is the same as $$val, which makes that the value of
$val is used as a variable name, say you

$hello=5;
$val="hello";
echo $$val; //will echo the $hello value


--

//Aho

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