Question

Edit: Made more clearer

I have a problem with a variable disappearing between function calls

firstly I start here with $pid being an int taken from a JSON string

print "PID".$pid."\n";
$a['points'] = Algorithm::getpredictionForPlayer($pid);

I get the output ‘PID12’ which is how it should be

Next in the Algorithm::getpredictionForPlayer

static function getpredictionForPlayer($pid)
{

            print "PID2:  ".$pid."\n";
    $points =0;

    for ($i = 0; $i < 10; $i++)
    {
    print "algorithm: ".$pid."\n";
        $points += v4::predictPointsForPlayer($pid);
    }

    return intval($points/10);
}

Occasionally i get ‘PID2: 12’, but more often all that prints is ‘PID2: ‘
Is there a reason the variable would disappear during this time?

Answer 1

Your variable in the global scope is $pid yet you are passing $player_id into the function

print "PID".$pid."\n";
$a['points'] = Algorithm::getpredictionForPlayer($player_id);

You’ve then got a parameter in your static method called $pid

static function getpredictionForPlayer($pid)

but this isn’t the same as the variable in your global scope. In fact this will take the same value as the $player_id that you are passing in. If you want the $pid variable from your global scope to exist in the static method you should pass it in instead of $player_id.

btw, you should think about whether you really need a static method. Generally they make things hard to test and should be avoided if possible. Should you have a player object and call the method getPrediction() on that?