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I have a Form object $form. One of its variables is a Field object which represents all fields and is an array (e.g $this->field['fieldname']). The getter is $form->fields().

To access a specific field method (to make it required or not for example) I use $form->fields()['fieldname'] which works on localhost with wamp but on the server throws this error:

Parse error: syntax error, unexpected '[' in (...)

I have PHP 5.3 on the server and because I reinstalled wamp and forgot to change it back to 5.3, wamp runs PHP 5.4. So I guess this is the reason for the error.

How can I access an object method, which returns an array, by the array key with PHP 5.3?

Davor
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    Use a temporary variable: `$fields = $form->fields; echo $fields['fieldname'];` – Jon Jul 09 '13 at 10:26
  • Just to explain what's going on here, this behaviour introduced in PHP 5.4 is called function array dereferencing. Documented [here](http://php.net/manual/en/migration54.new-features.php). – lonesomeday Jul 09 '13 at 10:27
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    possible duplicate of [5.4 dereferencing to valid 5.3 array call](http://stackoverflow.com/questions/14711654/5-4-dereferencing-to-valid-5-3-array-call) – feeela Jul 09 '13 at 10:28
  • more details in the PHP documentation: http://php.net/manual/en/language.types.array.php#example-88 – feeela Jul 09 '13 at 10:29
  • possible duplicate of [PHP syntax for dereferencing function result](http://stackoverflow.com/questions/742764/php-syntax-for-dereferencing-function-result) – cb0 Jul 09 '13 at 10:32
  • Cheers - I didn't know its name so couldn't find the other posts. – Davor Jul 09 '13 at 10:35

3 Answers3

3

Array dereferencing is possible as of PHP 5.4, not 5.3

PHP.net:

As of PHP 5.4 it is possible to array dereference the result of a function or method call directly. Before it was only possible using a temporary variable.

Karo
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  • thanks. Unfortunately that means I cannot modify my $form object (since the $form->fields() has a lot of setters) because using temporary variables would only be useful for display. – Davor Jul 09 '13 at 10:37
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Array dereferencing as described in the question is a feature that was only added in PHP 5.4. PHP 5.3 cannot do this.

echo $form->fields()['fieldname']

So this code will work in PHP 5.4 and higher.

In order to make this work in PHP 5.3, you need to do one of the following:

  1. Use a temporary variable:

    $temp = $form->fields()
echo $temp['fieldname'];

  2. Output the fields array as an object property rather than from a method:
    ie this....

    echo $form->fields['fieldname']

    ...is perfectly valid.

  3. Or, of course, you could upgrade your server to PHP 5.4. Bear in mind that 5.3 will be declared end-of-life relatively soon, now that 5.5 has been released, so you'll be wanting to upgrade sooner or later anyway; maybe this is your cue to do? (and don't worry about it; the upgrade path from 5.3 to 5.4 is pretty easy; there's nothing really that will break, except things that were deprecated anyway)

Spudley
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  • Cheers! I need to convince my host to give me 5.4, they only offer it for new accounts which is slightly ridiculous... – Davor Jul 09 '13 at 10:52
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As mentioned array dereferencing is only possible in 5.4 or greater. But you can save the object and later on access the fields:

$fields=$form->fields();
$value=$fields['fieldname']
...

AFAIK there is no other option.

cb0
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