src/Budkit/Validation/Validate.php
public static function isTimestamp($tstamp)
    {
        return ((string)(int)$tstamp === $tstamp)
        && ($tstamp <= PHP_INT_MAX)
        && ($tstamp >= ~PHP_INT_MAX);
    }
public static function isTimestamp($tstamp)
    {
        return ((string)(int)$tstamp === $tstamp)
        && ($tstamp <= PHP_INT_MAX)
        && ($tstamp >= ~PHP_INT_MAX);
    }
public static function isTimestamp ( $ tstamp ) { return ( ( string ) ( int ) $ tstamp === $ tstamp ) && ( $ tstamp <= PHP_INT_MAX ) && ( $ tstamp >= ~ PHP_INT_MAX ) ; }
Checks that a string is a timestamp

@param string $tstamp

@return boolean True if is timestamp, false if not;
Checks that a string is a timestamp