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    The NoRewindIterator class

    (PHP 5 >= 5.1.0, PHP 7, PHP 8)

    Introduction

    This iterator ignores rewind operations. This allows processing an iterator in multiple partial foreach loops.

    Class synopsis

    class NoRewindIterator extends IteratorIterator {
    /* Methods */
    public __construct(Iterator $iterator)
    public current(): mixed
    public key(): mixed
    public next(): void
    public rewind(): void
    public valid(): bool
    /* Inherited methods */
    public IteratorIterator::current(): mixed
    public IteratorIterator::getInnerIterator(): ?Iterator
    public IteratorIterator::key(): mixed
    public IteratorIterator::next(): void
    public IteratorIterator::rewind(): void
    public IteratorIterator::valid(): bool
    }

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    User Contributed Notes 1 note

    up
    7
    Anonymous
    4 years ago
    As its name implies, NoRewindIterator doesn't invoke the "rewind" method when It reaches the end of the iterator.

    Let's demonstrate it by two examles.

    In this example the "rewind" method will be invoked after when the "foreache" reaches its end, so, we can repeat printing the same values as many times as we want:

    <?PHP
    $iterator     = new ArrayIterator(['PHP', 'Python', 'Go']);

    foreach (    $iterator as $item) {
    echo     $item.PHP_EOL;
    }

    foreach (    $iterator as $item) {
    echo     $item.PHP_EOL;
    }
    ?>

    By using the NoRewindIterator, the "rewind" won't be invoked, so, we can't do as we did in previous example:

    <?PHP
    $iterator     = new ArrayIterator(['PHP', 'Python', 'Go']);
    $iterator = new NoRewindIterator($iterator);

    foreach (    $iterator as $item) {
    echo     $item.PHP_EOL;
    }

    // doesn't do anything
    foreach ($iterator as $item) {
    echo     $item.PHP_EOL;
    }

    ?>
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