Why Am I Getting the 'Strict standards: Only variables should be passed by reference' Warning in PHP?

Understanding the Strict Standards Warning: Only Variables Should Be Passed by Reference

When encountering the "Strict standards: Only variables should be passed by reference" warning, it's essential to comprehend the underlying cause and how to resolve it appropriately. This warning arises when an expression is passed by reference rather than a variable, as strict standards require.

In the given code snippet:

$el = array_shift($instance->find(..))

This code triggers the warning because $instance->find(...) is an expression that returns an array, not a variable. This behavior is not intuitive, as one might expect a method returning an array to be handled同樣地 a variable.

To address this error in strict mode, consider the following options:

• Modify the method's signature to remove the use of a reference:

function test_arr($a) {
    var_dump($a);
}

• If modifying the method's signature is not feasible, you can introduce an intermediate variable:

$inter = get_arr();
$el = array_shift($inter);

By understanding the nature of the warning and applying these solutions, you can resolve the issue effectively and adhere to strict standards.

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