function after ($this, $inthat)
{
if (!is_bool(strpos($inthat, $this)))
return substr($inthat, strpos($inthat,$this)+strlen($this));
};

function after_last ($this, $inthat)
{
if (!is_bool(strrevpos($inthat, $this)))
return substr($inthat, strrevpos($inthat, $this)+strlen($this));
};

function before ($this, $inthat)
{
return substr($inthat, 0, strpos($inthat, $this));
};

function before_last ($this, $inthat)
{''
return substr($inthat, 0, strrevpos($inthat, $this));
};

function between ($this, $that, $inthat)
{
return before($that, after($this, $inthat));
};

function between_last ($this, $that, $inthat)
{
return after_last($this, before_last($that, $inthat));
};

//posizione stringa al contrario
function strrevpos($instr, $needle)
{
    $rev_pos = strpos (strrev($instr), strrev($needle));
    if ($rev_pos===false) return false;
    else return strlen($instr) - $rev_pos - strlen($needle);
};

//multiple ricerche delle stringhe comprese
function multi_between($this, $that, $inthat)
{
$counter = 0;
    while ($inthat)
    {
        $counter++;
        $elements[$counter] = before($that, $inthat);
        $elements[$counter] = after($this, $elements[$counter]);
        $inthat = after($that, $inthat);
    }
	return $elements;
}