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Humph. I'm writing PHP (again) today. I'm just doing a bit of munging on
a data structure - basically turning a hash of objects some of which
have another object in the same hash as their parent into a tree
containing the same objects. It'd be trivial in Perl. In PHP it's not
quite so simple. PHP really likes every assignment to be a deep copy. In
mitigation it dangles the carrot of pretending to support references
using the =& assignment operator. Except that:
"Complex arrays are sometimes rather copied than referenced. Thus
following example will not work as expected." [1]
<?php
$top = array(
'A' => array(),
'B' => array(
'B_b' => array(),
),
);
$top['A']['parent'] = &$top;
$top['B']['parent'] = &$top;
$top['B']['B_b']['data'] = 'test';
print_r($top['A']['parent']['B']['B_b']); // array()
?>
There's plenty of madness elsewhere on the same page too. In PHP4
something as innocuous as
$obj = new Object();
actually makes a deep copy of the newly created object! So the idiom
is instead
$obj =& new Object();
Which is OK once you get used to the ugliness - but
"Since PHP 5, new return(sic) reference automatically so using =& in
this context is deprecated and produces E_STRICT level message."
So it's impossible to write code for something as simple as creating a
new object that works right in PHP4 and still works without warnings in
PHP5. Which of course means you give up on using E_STRICT, which means
you don't see all the other shite that's going on - some of which might
actually be informative.
Somebody remind me why do so many people use a language that can't even
get this completely basic stuff right.
[1] http://uk.php.net/manual/en/language.references.whatdo.php
(reposted from london.pm)
--
Andy Armstrong, hexten.net
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