PHP's Lack of Pointers

[neoform]

I've run into a problem which I don't think can be solved since php only has references and does not have pointers..

 

$GLOBALS['glob_var'] = 10;

funk($var);
echo 'SHOULD BE 10: '.$var.'<br />\n';

function funk(&$ref_var)
{
$ref_var = &$GLOBALS['glob_var'];
echo 'SHOULD BE 10: '.$ref_var.'<br />\n';
}

 

This outputs:

 

SHOULD BE 10: 10
SHOULD BE 10: 

 

Any ideas on how to fix this without duplicating the contents of $GLOBALS['glob_var'] ?

 

[hellbringer]

Use $GLOBALS without '&'.

[neoform]

Wouldn't that make a copy of the variable and not assign it to the reference?

[papaface]

What are you trying to do?

[alecks]

with global-ized variables or super globals like $GLOBALS it isn't necessary to reference them within a function, ex

 

$my_var = 12345;
echo $my_var;

function afunc() {
global $my_var;
$my_var = 23456;
}

afunc();

echo '<br />'.$my_var;

 

would output

 

12345

23456

 

References are useful when passing variables to functions and you want to modify them, ex:

 

$my_var = 12345;
echo $my_var;

function afunc(&$ref_to_my_var) {
$ref_to_my_var = 23456;
}

afunc($my_var);

echo '<br />'.$my_var;

 

will output

 

12345

23456

[neoform]

I'm using this purely as an example, my real code involves class member variables and they aren't integers, they're objects..  i just used this example to simplify it.

 

realistically, i want to pass a reference to the object without duplicating it (which would use up a lot more memory).

 

Maybe I wasn't clear enough before, I'm looking to pass back a reference..  this should work, but doesn't.

 

 

$GLOBALS['glob_var'] = 10;

funk($var);
echo 'SHOULD BE 10: '.$var."<br />\n";
$GLOBALS['glob_var'] = 11;
echo 'SHOULD BE 11: '.$var."<br />\n";

function funk(&$ref_var)
{
$ref_var = &$GLOBALS['glob_var'];
echo 'SHOULD BE 10: '.$ref_var."<br />\n";
}

[alecks]

$GLOBALS['glob_var'] = 10;

$var =& funk();
echo 'SHOULD BE 10: '.$var."<br />\n";
$GLOBALS['glob_var'] = 11;
echo 'SHOULD BE 11: '.$var."<br />\n";

function funk()
{
$ref_var = &$GLOBALS['glob_var'];
echo 'SHOULD BE 10: '.$ref_var."<br />\n";

return $ref_var
}

 

???

[neoform]

That's more along the line of what I'm trying to do, but this still gives a copy of the var, not a reference

 

$GLOBALS['glob_var'] = 10;

$var = & funk();
echo 'SHOULD BE 10: '.$var."<br />\n";
$GLOBALS['glob_var'] = 11;
echo 'SHOULD BE 11: '.$var."<br />\n";

function funk()
{
return $GLOBALS['glob_var'];
}

 

SHOULD BE 10: 10
SHOULD BE 11: 10

[discomatt]

<?php

$glob_var = 10;

funk($var);
echo 'SHOULD BE 10: '.$var."<br />\n";

function funk(&$ref_var)
{
$ref_var &= $GLOBALS['glob_var'];
echo 'SHOULD BE 10: '.$ref_var."<br />\n";
}

?>

 

Try that

 

BTW - need double quotes to parse \n as linebreak.

[neoform]

I'm not totally sure what $ref_var &= $GLOBALS['glob_var']; does, but my output is:

 

SHOULD BE 10: 0

SHOULD BE 10: 0

[rhodesa]

Objects are passed by reference