public function getRequired(string $key)
    {
        if (!isset($this->values[$key])) {
            throw new \RuntimeException(
                "the required config value '$key' was not found"
            );
        }
        return $this->values[$key];
    }
public function getRequired(string $key)
    {
        if (!isset($this->values[$key])) {
            throw new \RuntimeException(
                "the required config value '$key' was not found"
            );
        }
        return $this->values[$key];
    }
public function getRequired ( string $ key ) { if ( ! isset ( $ this -> values [ $ key ] ) ) { throw new \ RuntimeException ( "the required config value '$key' was not found" ) ; } return $ this -> values [ $ key ] ; }
Retrieve a value that must exist

@param string $key The key of the value to retrieve
@return mixed
@throws \RuntimeException If the key does not exist
Retrieve a value that must exist