<?php

function test($bool) {
    echo $bool ? 'true' : 'false';
    echo "\n";
}

$true = array(1, '1');
$false = array(0, '0');

echo "-- True --\n";
foreach ($true as $t) {
   test($t);
}

echo "\n-- False --\n";
foreach ($false as $f) {
   test($f);
}

-- True --
true
true

-- False --
false
false