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I have an array that relates mp3 files and their respective lengths in seconds

$playlist = array(  array("song" => "01.mp3","min" => "91"),
                   array("song" => "02.mp3","min" => "101"),
                   array("song" => "03.mp3","min" => "143"),
                   array("song" => "04.mp3","min" => "143"),
                   array("song" => "05.mp3","min" => "151")
            );

The I pluck a song from the playlist with array_rand()...

$song = $playlist[array_rand($playlist)];

Then, later on, I access the values from that array...

echo $song['song'];

//Then somewhere else...

echo $song['min'];

My question is, each time I request $song, is it going to produce a random result, or does it only produce a random result once per page load? (ie, once $song is defined, it's defined for good.) ...I'm hoping it's the latter.

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$song is assigned only at creation, it will remain the same for the remainder of that request / the variables lifetime. – Wrikken Apr 22 at 18:36
SCORE! Thank you. – tPlummer Apr 22 at 18:36
$song value intialize on on page load, not each time – Tamil Selvan Apr 22 at 18:37

1 Answer

up vote 1 down vote accepted

My question is, each time I request $song, is it going to produce a random result, or does it only produce a random result once per page load?

No, it won't. It will produce a random result every time you call the array_rand function. If you call it once per page load then yes, it will produce only one random result every time a page is loaded.

In general every time you access a variable you are most likely not going to change it in that specific line. In particular, simplifying your example (rand picks a number from the minimum to the maximum specified):

$x = rand(0, 9);

if a number, let's say 7, is picked then multiple accesses to $x will not change its value. Only an explicit $x = y assignment (or passing it to a class or function that has side effect on it) will possibly change its value.

Considering 7 to be picked from rand:

echo $x;
echo $x;
echo $x;

will print 777.

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