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Re-writing randomNumbers using a generator

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Our randomNumbers() function can be re-written to use a generator. 

<?php

function randomNumbers(int $length)
{
    for ($i = 0; $i < $length; $i++) {
        // yield tells the PHP interpreter that this value
        // should be the one used in the current iteration.
        yield mt_rand(1, 10);
    }
}

foreach (randomNumbers(10) as $number) {
    echo "$number\n";
}

Using a generator, we don’t have to build an entire list of random numbers to return from the function, leading to much less memory being used.

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Generators:
* Generators
* The Yield Keyword
* Reading a large file with a generator
* Why use a generator
* Using the send() function to pass values to a generator
* Re-writing randomNumbers using a generator
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