What best practices should be followed when using variables within a foreach loop in PHP?

When using variables within a foreach loop in PHP, it's important to ensure that the variable used to store the current value of the array element is not inadvertently modified within the loop. To prevent this, it's best practice to use a different variable name within the loop. This helps to avoid any unexpected behavior or errors that may arise from inadvertently modifying the loop control variable. 

// Incorrect way of using variables within a foreach loop
$numbers = [1, 2, 3, 4, 5];
foreach ($numbers as $number) {
    $number *= 2; // This will not modify the original array element
}
print_r($numbers); // Output: Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 )

// Correct way of using variables within a foreach loop
$numbers = [1, 2, 3, 4, 5];
foreach ($numbers as $num) {
    $doubledNum = $num * 2; // Use a different variable name
    echo $doubledNum . " "; // Output: 2 4 6 8 10
}

Keywords

foreach loop variables PHP array scope

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