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int	xmlXPathCastNodeSetToBoolean	(xmlNodeSetPtr ns)
Typedef xmlXPathObject * xmlXPathObjectPtr

int	xmlXPathIsNaN	(double val)
xmlXPathObjectPtr	xmlXPathConvertString	(xmlXPathObjectPtr val)
xmlXPathObjectPtr	xmlXPathConvertBoolean	(xmlXPathObjectPtr val)
xmlNodeSetPtr	xmlXPathNodeSetCreate	(xmlNodePtr val)
double	xmlXPathCastBooleanToNumber	(int val)
Variable double xmlXPathPINF

Function type: xmlXPathAxisFunc
xmlXPathObjectPtr	xmlXPathAxisFunc	(xmlXPathParserContextPtr ctxt, 
xmlXPathObjectPtr cur)

An axis traversal function. To traverse an axis, the engine calls the first time with cur == NULL and repeat until the function returns NULL indicating the end of the axis traversal.

ctxt:the XPath interpreter context
cur:the previous node being explored on that axis
Returns:the next node in that axis or NULL if at the end of the axis.

double	xmlXPathCastToNumber	(xmlXPathObjectPtr val)
int	xmlXPathCastStringToBoolean	(const xmlChar * val)
#define xmlXPathNodeSetItem

void	xmlXPathFreeObject	(xmlXPathObjectPtr obj)
Typedef xmlNodeSet * xmlNodeSetPtr

int	xmlXPathEvalPredicate	(xmlXPathContextPtr ctxt, 
xmlXPathObjectPtr res)
void	xmlXPathFreeContext	(xmlXPathContextPtr ctxt)
void	xmlXPathFreeNodeSetList	(xmlXPathObjectPtr obj)
xmlXPathObjectPtr	xmlXPathEval	(const xmlChar * str, 
xmlXPathContextPtr ctx)
Typedef xmlXPathAxis * xmlXPathAxisPtr

xmlXPathObjectPtr	xmlXPathConvertNumber	(xmlXPathObjectPtr val)
xmlChar *	xmlXPathCastNodeSetToString	(xmlNodeSetPtr ns)
xmlXPathObjectPtr	xmlXPathEvalExpression	(const xmlChar * str, 
xmlXPathContextPtr ctxt)
Variable double xmlXPathNINF

Structure xmlXPathVariable
struct _xmlXPathVariable { const xmlChar * name : the variable name xmlXPathObjectPtr value : the value }

xmlChar *	xmlXPathCastToString	(xmlXPathObjectPtr val)
xmlXPathObjectPtr	xmlXPathObjectCopy	(xmlXPathObjectPtr val)
xmlChar *	xmlXPathCastBooleanToString	(int val)
int	xmlXPathCastNumberToBoolean	(double val)
void	xmlXPathFreeNodeSet	(xmlNodeSetPtr obj)
xmlXPathContextPtr	xmlXPathNewContext	(xmlDocPtr doc)
#define xmlXPathNodeSetIsEmpty

Variable double xmlXPathNAN

Enum xmlXPathError {
    XPATH_EXPRESSION_OK = 0
    XPATH_NUMBER_ERROR = 1
    XPATH_UNFINISHED_LITERAL_ERROR = 2
    XPATH_START_LITERAL_ERROR = 3
    XPATH_VARIABLE_REF_ERROR = 4
    XPATH_UNDEF_VARIABLE_ERROR = 5
    XPATH_INVALID_PREDICATE_ERROR = 6
    XPATH_EXPR_ERROR = 7
    XPATH_UNCLOSED_ERROR = 8
    XPATH_UNKNOWN_FUNC_ERROR = 9
    XPATH_INVALID_OPERAND = 10
    XPATH_INVALID_TYPE = 11
    XPATH_INVALID_ARITY = 12
    XPATH_INVALID_CTXT_SIZE = 13
    XPATH_INVALID_CTXT_POSITION = 14
    XPATH_MEMORY_ERROR = 15
    XPTR_SYNTAX_ERROR = 16
    XPTR_RESOURCE_ERROR = 17
    XPTR_SUB_RESOURCE_ERROR = 18
    XPATH_UNDEF_PREFIX_ERROR = 19
    XPATH_ENCODING_ERROR = 20
    XPATH_INVALID_CHAR_ERROR = 21
}

int	xmlXPathCastToBoolean	(xmlXPathObjectPtr val)
Typedef xmlXPathVariable * xmlXPathVariablePtr

xmlChar *	xmlXPathCastNodeToString	(xmlNodePtr node)
Structure xmlXPathFunct
struct _xmlXPathFunct { const xmlChar * name : the function name xmlXPathEvalFunc func : the evaluation function }

Typedef xmlXPathCompExpr * xmlXPathCompExprPtr

Structure xmlXPathObject
struct _xmlXPathObject { xmlXPathObjectType type xmlNodeSetPtr nodesetval int boolval double floatval xmlChar * stringval void * user int index void * user2 int index2 }

long	xmlXPathOrderDocElems	(xmlDocPtr doc)
#define xmlXPathNodeSetGetLength

double	xmlXPathCastNodeToNumber	(xmlNodePtr node)
double	xmlXPathCastStringToNumber	(const xmlChar * val)
Structure xmlXPathContext
struct _xmlXPathContext { xmlDocPtr doc : The current document xmlNodePtr node : The current node int nb_variables_unused : unused (hash table) int max_variables_unused : unused (hash table) xmlHashTablePtr varHash : Hash table of defined variables int nb_types : number of defined types int max_types : max number of types xmlXPathTypePtr types : Array of defined types int nb_funcs_unused : unused (hash table) int max_funcs_unused : unused (hash table) xmlHashTablePtr funcHash : Hash table of defined funcs int nb_axis : number of defined axis int max_axis : max number of axis xmlXPathAxisPtr axis : Array of defined axis the namespace nodes of the xmlNsPtr * namespaces : Array of namespaces int nsNr : number of namespace in scope void * user : function to free extra variables int contextSize : the context size int proximityPosition : the proximity position extra stuff for XPointer int xptr : it this an XPointer context xmlNodePtr here : for here() xmlNodePtr origin : for origin() the set of namespace declarations in xmlHashTablePtr nsHash : The namespaces hash table void * varLookupFunc : variable lookup func void * varLookupData : variable lookup data Possibility to link in an ex void * extra : needed for XSLT The function name and URI when ca const xmlChar * function const xmlChar * functionURI : function lookup function and data void * funcLookupFunc : function lookup func void * funcLookupData : function lookup data temporary namespace lists ke xmlNsPtr * tmpNsList : Array of namespaces int tmpNsNr : number of namespace in scope error reporting mech void * userData : user specific data block xmlStructuredErrorFunc error : the callback in case of errors xmlError lastError : the last error xmlNodePtr debugNode : the source node XSLT }

Structure xmlXPathParserContext
struct _xmlXPathParserContext { const xmlChar * cur : the current char being parsed const xmlChar * base : the full expression int error : error code xmlXPathContextPtr context : the evaluation context xmlXPathObjectPtr value : the current value int valueNr : number of values stacked int valueMax : max number of values stacked xmlXPathObjectPtr * valueTab : stack of values xmlXPathCompExprPtr comp : the precompiled expression int xptr : it this an XPointer expression xmlNodePtr ancestor : used for walking preceding axis }

Typedef xmlXPathType * xmlXPathTypePtr

Structure xmlXPathType
struct _xmlXPathType { const xmlChar * name : the type name xmlXPathConvertFunc func : the conversion function }

int	xmlXPathIsInf	(double val)
Structure xmlXPathAxis
struct _xmlXPathAxis { const xmlChar * name : the axis name xmlXPathAxisFunc func : the search function }

xmlXPathObjectPtr	xmlXPathCompiledEval	(xmlXPathCompExprPtr comp, 
xmlXPathContextPtr ctx)
Structure xmlNodeSet
struct _xmlNodeSet { int nodeNr : number of nodes in the set int nodeMax : size of the array as allocated xmlNodePtr * nodeTab : array of nodes in no particular order @@ with_ns }

Typedef xmlXPathFunct * xmlXPathFuncPtr

Function type: xmlXPathConvertFunc
int	xmlXPathConvertFunc	(xmlXPathObjectPtr obj, 
int type)

A conversion function is associated to a type and used to cast the new type to primitive values.

obj:an XPath object
type:the number of the target type
Returns:-1 in case of error, 0 otherwise

void	xmlXPathInit	(void)
int	xmlXPathCmpNodes	(xmlNodePtr node1, 
xmlNodePtr node2)
xmlChar *	xmlXPathCastNumberToString	(double val)
Function type: xmlXPathEvalFunc
void	xmlXPathEvalFunc	(xmlXPathParserContextPtr ctxt, 
int nargs)

An XPath evaluation function, the parameters are on the XPath context stack.

ctxt:an XPath parser context
nargs:the number of arguments passed to the function

Function type: xmlXPathFunction
void	xmlXPathFunction	(xmlXPathParserContextPtr ctxt, 
int nargs)

An XPath function. The arguments (if any) are popped out from the context stack and the result is pushed on the stack.

ctxt:the XPath interprestation context
nargs:the number of arguments

void	xmlXPathFreeCompExpr	(xmlXPathCompExprPtr comp)
Typedef xmlXPathParserContext * xmlXPathParserContextPtr

Structure xmlXPathCompExpr
struct _xmlXPathCompExpr { The content of this structure is not made public by the API. }

Typedef xmlXPathContext * xmlXPathContextPtr

xmlXPathCompExprPtr	xmlXPathCompile	(const xmlChar * str)
double	xmlXPathCastNodeSetToNumber	(xmlNodeSetPtr ns)
Enum xmlXPathObjectType {
    XPATH_UNDEFINED = 0
    XPATH_NODESET = 1
    XPATH_BOOLEAN = 2
    XPATH_NUMBER = 3
    XPATH_STRING = 4
    XPATH_POINT = 5
    XPATH_RANGE = 6
    XPATH_LOCATIONSET = 7
    XPATH_USERS = 8
    XPATH_XSLT_TREE = 9 : An XSLT value tree, non modifiable
}

Description

Function: xmlXPathCastNodeSetToBoolean

int	xmlXPathCastNodeSetToBoolean	(xmlNodeSetPtr ns)

Converts a node-set to its boolean value

ns:a node-set
Returns:the boolean value

Function: xmlXPathIsNaN

int	xmlXPathIsNaN	(double val)

Provides a portable isnan() function to detect whether a double is a NotaNumber. Based on trio code http://sourceforge.net/projects/ctrio/

val:a double value
Returns:1 if the value is a NaN, 0 otherwise

Function: xmlXPathConvertString

xmlXPathObjectPtr	xmlXPathConvertString	(xmlXPathObjectPtr val)

Converts an existing object to its string() equivalent

val:an XPath object
Returns:the new object, the old one is freed (or the operation is done directly on @val)

Function: xmlXPathConvertBoolean

xmlXPathObjectPtr	xmlXPathConvertBoolean	(xmlXPathObjectPtr val)

Converts an existing object to its boolean() equivalent

val:an XPath object
Returns:the new object, the old one is freed (or the operation is done directly on @val)

Function: xmlXPathNodeSetCreate

xmlNodeSetPtr	xmlXPathNodeSetCreate	(xmlNodePtr val)

Create a new xmlNodeSetPtr of type double and of value @val

val:an initial xmlNodePtr, or NULL
Returns:the newly created object.

Function: xmlXPathCastBooleanToNumber

double	xmlXPathCastBooleanToNumber	(int val)

Converts a boolean to its number value

val:a boolean
Returns:the number value
An axis traversal function. To traverse an axis, the engine calls the first time with cur == NULL and repeat until the function returns NULL indicating the end of the axis traversal.

Function: xmlXPathCastToNumber

double	xmlXPathCastToNumber	(xmlXPathObjectPtr val)

Converts an XPath object to its number value

val:an XPath object
Returns:the number value

Function: xmlXPathCastStringToBoolean

int	xmlXPathCastStringToBoolean	(const xmlChar * val)

Converts a string to its boolean value

val:a string
Returns:the boolean value

Macro: xmlXPathNodeSetItem

#define xmlXPathNodeSetItem

Implements a functionality similar to the DOM NodeList.item(). Returns the xmlNodePtr at the given @index in @ns or NULL if @index is out of range (0 to length-1)

Function: xmlXPathFreeObject

void	xmlXPathFreeObject	(xmlXPathObjectPtr obj)

Free up an xmlXPathObjectPtr object.

obj:the object to free

Function: xmlXPathEvalPredicate

int	xmlXPathEvalPredicate	(xmlXPathContextPtr ctxt, 
xmlXPathObjectPtr res)

Evaluate a predicate result for the current node. A PredicateExpr is evaluated by evaluating the Expr and converting the result to a boolean. If the result is a number, the result will be converted to true if the number is equal to the position of the context node in the context node list (as returned by the position function) and will be converted to false otherwise; if the result is not a number, then the result will be converted as if by a call to the boolean function.

ctxt:the XPath context
res:the Predicate Expression evaluation result
Returns:1 if predicate is true, 0 otherwise

Function: xmlXPathFreeContext

void	xmlXPathFreeContext	(xmlXPathContextPtr ctxt)

Free up an xmlXPathContext

ctxt:the context to free

Function: xmlXPathFreeNodeSetList

void	xmlXPathFreeNodeSetList	(xmlXPathObjectPtr obj)

Free up the xmlXPathObjectPtr @obj but don't deallocate the objects in the list contrary to xmlXPathFreeObject().

obj:an existing NodeSetList object

Function: xmlXPathEval

xmlXPathObjectPtr	xmlXPathEval	(const xmlChar * str, 
xmlXPathContextPtr ctx)

Evaluate the XPath Location Path in the given context.

str:the XPath expression
ctx:the XPath context
Returns:the xmlXPathObjectPtr resulting from the evaluation or NULL. the caller has to free the object.

Function: xmlXPathConvertNumber

xmlXPathObjectPtr	xmlXPathConvertNumber	(xmlXPathObjectPtr val)

Converts an existing object to its number() equivalent

val:an XPath object
Returns:the new object, the old one is freed (or the operation is done directly on @val)

Function: xmlXPathCastNodeSetToString

xmlChar *	xmlXPathCastNodeSetToString	(xmlNodeSetPtr ns)

Converts a node-set to its string value.

ns:a node-set
Returns:a newly allocated string.

Function: xmlXPathEvalExpression

xmlXPathObjectPtr	xmlXPathEvalExpression	(const xmlChar * str, 
xmlXPathContextPtr ctxt)

Evaluate the XPath expression in the given context.

str:the XPath expression
ctxt:the XPath context
Returns:the xmlXPathObjectPtr resulting from the evaluation or NULL. the caller has to free the object.

Function: xmlXPathCastToString

xmlChar *	xmlXPathCastToString	(xmlXPathObjectPtr val)

Converts an existing object to its string() equivalent

val:an XPath object
Returns:the string value of the object, NULL in case of error. A new string is allocated only if needed (@val isn't a string object).

Function: xmlXPathObjectCopy

xmlXPathObjectPtr	xmlXPathObjectCopy	(xmlXPathObjectPtr val)

allocate a new copy of a given object

val:the original object
Returns:the newly created object.

Function: xmlXPathCastBooleanToString

xmlChar *	xmlXPathCastBooleanToString	(int val)

Converts a boolean to its string value.

val:a boolean
Returns:a newly allocated string.

Function: xmlXPathCastNumberToBoolean

int	xmlXPathCastNumberToBoolean	(double val)

Converts a number to its boolean value

val:a number
Returns:the boolean value

Function: xmlXPathFreeNodeSet

void	xmlXPathFreeNodeSet	(xmlNodeSetPtr obj)

Free the NodeSet compound (not the actual nodes !).

obj:the xmlNodeSetPtr to free

Function: xmlXPathNewContext

xmlXPathContextPtr	xmlXPathNewContext	(xmlDocPtr doc)

Create a new xmlXPathContext

doc:the XML document
Returns:the xmlXPathContext just allocated. The caller will need to free it.

Macro: xmlXPathNodeSetIsEmpty

#define xmlXPathNodeSetIsEmpty

Checks whether @ns is empty or not. Returns %TRUE if @ns is an empty node-set.

Function: xmlXPathCastToBoolean

int	xmlXPathCastToBoolean	(xmlXPathObjectPtr val)

Converts an XPath object to its boolean value

val:an XPath object
Returns:the boolean value

Function: xmlXPathCastNodeToString

xmlChar *	xmlXPathCastNodeToString	(xmlNodePtr node)

Converts a node to its string value.

node:a node
Returns:a newly allocated string.

Function: xmlXPathOrderDocElems

long	xmlXPathOrderDocElems	(xmlDocPtr doc)

Call this routine to speed up XPath computation on static documents. This stamps all the element nodes with the document order Like for line information, the order is kept in the element->content field, the value stored is actually - the node number (startting at -1) to be able to differenciate from line numbers.

doc:an input document
Returns:the number of element found in the document or -1 in case of error.

Macro: xmlXPathNodeSetGetLength

#define xmlXPathNodeSetGetLength

Implement a functionality similar to the DOM NodeList.length. Returns the number of nodes in the node-set.

Function: xmlXPathCastNodeToNumber

double	xmlXPathCastNodeToNumber	(xmlNodePtr node)

Converts a node to its number value

node:a node
Returns:the number value

Function: xmlXPathCastStringToNumber

double	xmlXPathCastStringToNumber	(const xmlChar * val)

Converts a string to its number value

val:a string
Returns:the number value

Function: xmlXPathIsInf

int	xmlXPathIsInf	(double val)

Provides a portable isinf() function to detect whether a double is a +Infinite or -Infinite. Based on trio code http://sourceforge.net/projects/ctrio/

val:a double value
Returns:1 vi the value is +Infinite, -1 if -Infinite, 0 otherwise

Function: xmlXPathCompiledEval

xmlXPathObjectPtr	xmlXPathCompiledEval	(xmlXPathCompExprPtr comp, 
xmlXPathContextPtr ctx)

Evaluate the Precompiled XPath expression in the given context.

comp:the compiled XPath expression
ctx:the XPath context
Returns:the xmlXPathObjectPtr resulting from the evaluation or NULL. the caller has to free the object.
A conversion function is associated to a type and used to cast the new type to primitive values.

Function: xmlXPathInit

void	xmlXPathInit	(void)

Initialize the XPath environment

Function: xmlXPathCmpNodes

int	xmlXPathCmpNodes	(xmlNodePtr node1, 
xmlNodePtr node2)

Compare two nodes w.r.t document order

node1:the first node
node2:the second node
Returns:-2 in case of error 1 if first point < second point, 0 if that's the same node, -1 otherwise

Function: xmlXPathCastNumberToString

xmlChar *	xmlXPathCastNumberToString	(double val)

Converts a number to its string value.

val:a number
Returns:a newly allocated string.
An XPath evaluation function, the parameters are on the XPath context stack. An XPath function. The arguments (if any) are popped out from the context stack and the result is pushed on the stack.

Function: xmlXPathFreeCompExpr

void	xmlXPathFreeCompExpr	(xmlXPathCompExprPtr comp)

Free up the memory allocated by @comp

comp:an XPATH comp

Function: xmlXPathCompile

xmlXPathCompExprPtr	xmlXPathCompile	(const xmlChar * str)

Compile an XPath expression

str:the XPath expression
Returns:the xmlXPathCompExprPtr resulting from the compilation or NULL. the caller has to free the object.

Function: xmlXPathCastNodeSetToNumber

double	xmlXPathCastNodeSetToNumber	(xmlNodeSetPtr ns)

Converts a node-set to its number value

ns:a node-set
Returns:the number value

Daniel Veillard