Why is Assigning by Reference from the Return Value of \'new\' Expression Deprecated in PHP?

Deprecated Assigning by Reference

In earlier versions of PHP, it was common practice to assign objects and other data structures by reference using the "&" operator. However, this practice has been deprecated in PHP5 and higher. When attempting to assign the return value of a "new" expression by reference, developers may encounter the error message "Assigning the return value of new by reference is deprecated."

The Deprecation Reason

The deprecation of assigning by reference from a "new" expression is intended to enhance code maintainability and performance. By default, objects created using "new" are passed by value, ensuring that each object has its own memory space. Assigning by reference can lead to confusion and unexpected side effects when working with multiple objects, as updates made to one object may accidentally affect other objects sharing the same reference.

Error Resolution

To resolve this issue, simply remove the "&" operator from the assignment statement. The following code is valid in PHP5 and higher:

<code class="php">$obj_md = new MDB2();</code>

If the error persists even after removing the "&" operator, check your code for potential syntax errors or conflicts with other PHP settings. Some PHP configurations may still allow deprecated features, so it's recommended to verify your error_reporting settings in your php.ini file.

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