lib/AdobeMarketingCloud/OptionParser.php
public function __isset($flag)
    {
        try {
            $this->checkFlag($flag);
        } catch (\Exception $e) {
            return false;
        }

        $ruleIndex = $this->_flags[$flag];

        return isset($this->_options[$ruleIndex]);
    }
public function __isset($flag)
    {
        try {
            $this->checkFlag($flag);
        } catch (\Exception $e) {
            return false;
        }

        $ruleIndex = $this->_flags[$flag];

        return isset($this->_options[$ruleIndex]);
    }
Returns true if an option for the given flag is set.

@return  bool