protected function create_key() {
		if ( is_array( $this->data ) ) {
			$this->data[ $this->key ] = null;
		} elseif ( is_object( $this->data ) ) {
			$this->data->{$this->key} = null;
		} else {
			$type = gettype( $this->data );
			throw new UnexpectedValueException(
				"Cannot create key \"{$this->key}\" on data type {$type}"
			);
		}
	}
protected function create_key() {
		if ( is_array( $this->data ) ) {
			$this->data[ $this->key ] = null;
		} elseif ( is_object( $this->data ) ) {
			$this->data->{$this->key} = null;
		} else {
			$type = gettype( $this->data );
			throw new UnexpectedValueException(
				"Cannot create key \"{$this->key}\" on data type {$type}"
			);
		}
	}
protected function create_key ( ) { if ( is_array ( $ this -> data ) ) { $ this -> data [ $ this -> key ] = null ; } elseif ( is_object ( $ this -> data ) ) { $ this -> data -> { $ this -> key } = null ; } else { $ type = gettype ( $ this -> data ) ; throw new UnexpectedValueException ( "Cannot create key \"{$this->key}\" on data type {$type}" ) ; } }
Create the key on the current data.

@throws UnexpectedValueException
Create the key on the current data .