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POPHP referencing array instead of copying
 

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  1. POPHP referencing array instead of copying
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    <p>I have an array, I need to copy the first item in the array and alter it.</p> <p>This is what i'm doing:</p> <pre><code>echo $QuantityDiscounts[0]['price'] . '&lt;br&gt;'; echo $QuantityDiscounts[0]['from_quantity'] . '&lt;br&gt;'; $firstItem = $QuantityDiscounts[0]; $firstItem['from_quantity'] = 999; $firstItem['price'] = 999; echo $QuantityDiscounts[0]['price'] . '&lt;br&gt;'; echo $QuantityDiscounts[0]['from_quantity'] . '&lt;br&gt;'; </code></pre> <p>This is the output this gives me:</p> <pre><code>4.870000 10 4.870000 999 </code></pre> <p>When I change the value of the copied array it's changing the original array. What makes this even stranger is that it only happens for the 'from_quantity' item. As you can see the 'price' element remains unaltered.</p> <p>I can't figure out why this is happening, as you can see i'm not using references. Is there an explanation for this behaviour that i'm missing?</p> <p>Some more info:</p> <p>If I first copy the 'from_quantity' in the original array so that it uses a different key this behaviour goes away.</p> <pre><code>$QuantityDiscounts[0]['test'] = $QuantityDiscounts[0]['from_quantity']; echo $QuantityDiscounts[0]['price'] . '&lt;br&gt;'; echo $QuantityDiscounts[0]['from_quantity'] . '&lt;br&gt;'; echo $QuantityDiscounts[0]['test'] . '&lt;br&gt;'; $firstItem = $QuantityDiscounts[0]; $firstItem['from_quantity'] = 999; $firstItem['test'] = 999; $firstItem['price'] = 999; echo $QuantityDiscounts[0]['price'] . '&lt;br&gt;'; echo $QuantityDiscounts[0]['from_quantity'] . '&lt;br&gt;'; echo $QuantityDiscounts[0]['test'] . '&lt;br&gt;'; </code></pre> <p>Outputs:</p> <pre><code>4.870000 10 10 4.870000 999 10 </code></pre> <p>** UPDATE ** - Thanks for your help so far</p> <p>Here is the function that generates the array. I can see that a reference is being used there which must be causing the problems. Does this mean I can't copy and modify the 'from_quantity' without changing the original?</p> <pre><code>protected function formatQuantityDiscounts($specific_prices, $price, $tax_rate, $ecotax_amount) { foreach ($specific_prices as $key =&gt; &amp;$row) { $row['quantity'] = &amp;$row['from_quantity']; if ($row['price'] &gt;= 0) // The price may be directly set { $cur_price = (Product::$_taxCalculationMethod == PS_TAX_EXC ? $row['price'] : $row['price'] * (1 + $tax_rate / 100)) + (float)$ecotax_amount; if ($row['reduction_type'] == 'amount') $cur_price -= (Product::$_taxCalculationMethod == PS_TAX_INC ? $row['reduction'] : $row['reduction'] / (1 + $tax_rate / 100)); else $cur_price *= 1 - $row['reduction']; $row['real_value'] = $price - $cur_price; } else { if ($row['reduction_type'] == 'amount') $row['real_value'] = Product::$_taxCalculationMethod == PS_TAX_INC ? $row['reduction'] : $row['reduction'] / (1 + $tax_rate / 100); else $row['real_value'] = $row['reduction'] * 100; } $row['nextQuantity'] = (isset($specific_prices[$key + 1]) ? (int)$specific_prices[$key + 1]['from_quantity'] : -1); } return $specific_prices; } </code></pre>
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    1. COI just made a phpfiddle and tried it and it's not referencing for me - http://phpfiddle.org/main/code/b8g-03e You must be doing something else.
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      1. USDan Goodspeed
    2. COwhich version of php ? please provide a full code we can copy/paste to test
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      1. USAsenar
    3. COPossibly the OP is doing something like this: http://phpfiddle.org/main/code/naj-0gu
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      1. USKaii
 

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