Description:
------------
---
From manual page: http://www.php.net/function.unset
---

Does not explicitly mention whether a construct like

// Now delete every item, but leave the array itself intact:
foreach ($array as $i => $value) {
    unset($array[$i]);
}

is safe, even though it's implied since that example comes from a (non-user-contributed) note in http://www.php.net/language.types.array


You should probably also mention that this does not hold for 'for' loops unless the size of array is captured first. e.g. this is bad:

for ($i = 0; $i < count($a); $i++) {
    if (!sometest($a[$i])) {
        unset($a[$i]);
    }
}

but this is okay:

for ($i = 0, $n = count($a); $i < $n; $i++) {
    if (!sometest($a[$i])) {
        unset($a[$i]);
    }
}