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Date: Wed, 19 Dec 2012 20:30:59 -0800
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Subject: Re: [PHP-DEV] Extension for str_replace / preg_replace with arrays
From: christopher.jones@oracle.com (Christopher Jones)



On 12/19/2012 03:18 PM, Larry Garfield wrote:
> You could likely simplify the code even further using an infinite iterator:
>
> http://us1.php.net/infiniteiterator
>
> $result = preg_replace_callback(
>      '/word/',
>      function($matches) use (&$replacements_iterator) {
>          return $replacements->next();
>      },
>      'word word word word word'
> );
>
> --Larry Garfield
>

What am I missing that causes the first call to $replacements_iterator->current() to return NULL
unless the iterator is rewound before use?

Chris

------------------

<?php

$replacements = array(
     'one', 'two', 'three'
);

$replacements_iterator = new InfiniteIterator(new ArrayIterator($replacements));
$replacements_iterator->rewind();  // why is the rewind needed?

$result = preg_replace_callback(
     '/word/',
     function($matches) use ($replacements_iterator) {
         $r = $replacements_iterator->current();
         $replacements_iterator->next();
         return $r;
     },
     'word word word word word'
);

var_dump($result);

// Outputs:
//    string(21) "one two three one two"
// Without the call to $replacements_iterator->rewind(), the output is:
//    string(18) " two three one two"

?>

-- 
christopher.jones@oracle.com  http://twitter.com/ghrd