xpath

Documentation

Index

• Constants
• func Check(path string) (err error)
• func ClearScope(ctxt unsafe.Pointer)
• func SetScope(ctxt unsafe.Pointer, v VariableScope)
• func ValueToXPathObject(val interface{}) (ret C.xmlXPathObjectPtr)
• func XPathObjectToValue(obj C.xmlXPathObjectPtr) (result interface{})
• type Expression
  • func Compile(path string) (expr *Expression)
  • func (exp *Expression) Free()
  • func (exp *Expression) String() string
• type VariableScope
  • func GetScope(ctxt unsafe.Pointer) VariableScope
• type XPath
  • func NewXPath(docPtr unsafe.Pointer) (xpath *XPath)
  • func (xpath *XPath) Evaluate(nodePtr unsafe.Pointer, xpathExpr *Expression) (err error)
  • func (xpath *XPath) EvaluateAsNodeset(nodePtr unsafe.Pointer, xpathExpr *Expression) (nodes []unsafe.Pointer, err error)
  • func (xpath *XPath) Free()
  • func (xpath *XPath) GetContextPosition() (position, size int)
  • func (xpath *XPath) RegisterNamespace(prefix, href string) bool
  • func (xpath *XPath) ResultAsBoolean() (val bool, err error)
  • func (xpath *XPath) ResultAsNodeset() (nodes []unsafe.Pointer, err error)
  • func (xpath *XPath) ResultAsNumber() (val float64, err error)
  • func (xpath *XPath) ResultAsString() (val string, err error)
  • func (xpath *XPath) ReturnType() XPathObjectType
  • func (xpath *XPath) SetContextPosition(position, size int)
  • func (xpath *XPath) SetResolver(v VariableScope)
• type XPathFunction
• type XPathObjectType

Constants

const (
	XPATH_UNDEFINED   XPathObjectType = 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
)

Functions

func Check

func Check(path string) (err error)

func ClearScope

func ClearScope(ctxt unsafe.Pointer)

func SetScope

func SetScope(ctxt unsafe.Pointer, v VariableScope)

func ValueToXPathObject

func ValueToXPathObject(val interface{}) (ret C.xmlXPathObjectPtr)

Convert an arbitrary value into a C.xmlXPathObjectPtr Unrecognised and nil values are converted to empty node sets.

func XPathObjectToValue

func XPathObjectToValue(obj C.xmlXPathObjectPtr) (result interface{})

Types

type Expression

type Expression struct {
	Ptr *C.xmlXPathCompExpr
	// contains filtered or unexported fields
}

func Compile

func Compile(path string) (expr *Expression)

func (*Expression) Free

func (exp *Expression) Free()

func (*Expression) String

func (exp *Expression) String() string

type VariableScope

type VariableScope interface {
	ResolveVariable(string, string) interface{}
	IsFunctionRegistered(string, string) bool
	ResolveFunction(string, string) XPathFunction
}

Types that provide the VariableScope interface know how to resolve XPath variable names into values.

This interface exist primarily for the benefit of XSLT processors.

func GetScope

func GetScope(ctxt unsafe.Pointer) VariableScope

type XPath

type XPath struct {
	ContextPtr *C.xmlXPathContext
	ResultPtr  *C.xmlXPathObject
}

func NewXPath

func NewXPath(docPtr unsafe.Pointer) (xpath *XPath)

func (*XPath) Evaluate

func (xpath *XPath) Evaluate(nodePtr unsafe.Pointer, xpathExpr *Expression) (err error)

Evaluate an XPath. The returned result is stored in the struct. Call ReturnType to discover the type of result, and call one of the ResultAs* functions to return a copy of the result as a particular type.

func (*XPath) EvaluateAsNodeset

func (xpath *XPath) EvaluateAsNodeset(nodePtr unsafe.Pointer, xpathExpr *Expression) (nodes []unsafe.Pointer, err error)

Evaluate an XPath and attempt to consume the result as a nodeset.

func (*XPath) Free

func (xpath *XPath) Free()

func (*XPath) GetContextPosition

func (xpath *XPath) GetContextPosition() (position, size int)

GetContextPosition retrieves the internal values used to determine the values of position() and last() for the current context node.

This allows values to saved and restored during processing of a document.

func (*XPath) RegisterNamespace

func (xpath *XPath) RegisterNamespace(prefix, href string) bool

func (*XPath) ResultAsBoolean

func (xpath *XPath) ResultAsBoolean() (val bool, err error)

Coerce the result into a boolean

func (*XPath) ResultAsNodeset

func (xpath *XPath) ResultAsNodeset() (nodes []unsafe.Pointer, err error)

Get the XPath result as a nodeset.

func (*XPath) ResultAsNumber

func (xpath *XPath) ResultAsNumber() (val float64, err error)

Coerce the result into a number

func (*XPath) ResultAsString

func (xpath *XPath) ResultAsString() (val string, err error)

Coerce the result into a string

func (*XPath) ReturnType

func (xpath *XPath) ReturnType() XPathObjectType

Determine the actual return type of the XPath evaluation.

func (*XPath) SetContextPosition

func (xpath *XPath) SetContextPosition(position, size int)

SetContextPosition sets the internal values needed to determine the values of position() and last() for the current context node.

func (*XPath) SetResolver

func (xpath *XPath) SetResolver(v VariableScope)

Add a variable resolver.

type XPathFunction

type XPathFunction func(context VariableScope, args []interface{}) interface{}

type XPathObjectType

type XPathObjectType int