toFn := func(name string) (func([]byte, string) []byte, func([]byte, []byte) []byte) {
		switch name {
		case "Trim":
			return Trim, nil
		case "TrimLeft":
			return TrimLeft, nil
		case "TrimRight":
			return TrimRight, nil
		case "TrimPrefix":
			return nil, TrimPrefix
		case "TrimSuffix":
			return nil, TrimSuffix
		default:
			t.Errorf("Undefined trim function %s", name)