// Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).

 // All rights reserved.

 // This component and the accompanying materials are made available

 // under the terms of "Eclipse Public License v1.0"

 // which accompanies this distribution, and is available

 // at the URL "http://www.eclipse.org/legal/epl-v10.html".

 //

 // Initial Contributors:

 // Nokia Corporation - initial contribution.

 //

 // Contributors:

 //

 // Description:

 // Result of XPath expression

 //

 /**

  @file

  @publishedAll

  @released

 */

 #ifndef XMLENGXPATHRESULT_H

 #define XMLENGXPATHRESULT_H

 #include <xml/dom/xmlengnodeset.h>

 /**

 Represents the result of a XPath expression.

 The result may be one of the standard types: string, boolean, number (float), 

 node set or be undefined in the case of error.

 The returned result should be freed after use.

 */

 class RXmlEngXPathResult

 {

 	friend class RXmlEngXPathExpression;

     friend class TXmlEngXPathEvaluationContextImpl;

 public:

     /**

 	Result types of a XPath expression.

 	See http://w3.org/TR/xpath#section-Introduction

     */

     enum TXmlEngXPathResultType

         {

         EUndefined = 0,

         ENodeset = 1,

         EBoolean = 2,

         ENumber = 3,

         EString = 4

         //Other node types defined in XPath are not supported.

 	    } ;

 public:

 	/** Default constructor */

 	IMPORT_C RXmlEngXPathResult();

 	/** Frees any allocated memory */

 	IMPORT_C void Free();

 	/** Frees any allocated memory */

 	inline void Close();

 	/**

 	Retrieves the type of the result (e.g. boolean, number, string, etc.).  

 	The type of a result should always be checked before using the result.

 	If there was an error and no value was set, undefined is returned.

 	Otherwise nodeset is returned.	

 	@return Type of result.

 	@see TXmlEngXPathResultType

 	*/

 	IMPORT_C TXmlEngXPathResultType Type() const;

 	/**

 	Retrieves a node-set result.  A Non-RXmlEngNodeSet result will return NULL.

 	No conversion is done from other types.

 	For more information no NULL nodes:

 	@see TXmlEngNode

 	@return Node-set result

 	*/

 	IMPORT_C RXmlEngNodeSet AsNodeSet() const;

 	/**

 	Retrieves a string copy of result.

 	@param A buffer allocated by the caller that holds the result string

 	@leave KErrNoMemory if out of memory situation occurs.

 	@leave - Otherwise any of the system wide errors.

 	*/	

 	IMPORT_C void AsStringL(RBuf8& aOutput) const;

 	/**

 	Retrieves a numeric value result.  Conversion can occur from other types.

 	Node sets, strings, and booleans will be cast to numbers.  Anything else

 	will return NAN (i.e. not a number).

 	@return Numeric value of the result.

 	@see Math

 	*/	

 	IMPORT_C TReal AsNumber() const;

 	/**

 	Retrieves a boolean result.  Conversion can occur from other types.

 	Numbers will be returned as true unless it is not a number or 0.0.

 	A string of 0 length will return false, otherwise true.

 	If the node exists it will be returned as true, otherwise false.

 	@return Boolean value of the result

 	*/	

 	IMPORT_C TBool AsBoolean() const;

 private:

 	/**

 	Constructor

 	@param aData Internal representation of XPath result

 	*/

 	RXmlEngXPathResult(void* aData);

 private: 

 	void* iInternal;

     };	

 #include <xml/dom/xmlengxpathresult.inl>

 #endif /* XMLENGXPATHRESULT_H */