public function get(string $key)
    {
        if (!$this->has($key)) {
            throw new \InvalidArgumentException(\sprintf('The value identified by "%s" does not exist.', $key));
        }

        return $this->values[$key];
    }
public function get(string $key)
    {
        if (!$this->has($key)) {
            throw new \InvalidArgumentException(\sprintf('The value identified by "%s" does not exist.', $key));
        }

        return $this->values[$key];
    }
public function get ( string $ key ) { if ( ! $ this -> has ( $ key ) ) { throw new \ InvalidArgumentException ( \ sprintf ( 'The value identified by "%s" does not exist.' , $ key ) ) ; } return $ this -> values [ $ key ] ; }
Get the value with a specific key.

@param string $key The key

@throws \InvalidArgumentException

@return mixed|null
Get the value with a specific key .