VariableSubstitutionTransformer Class

An optimiser for walking algebra and expression trees and replacing a Variable with another Variable or a Constant.

Inheritance Hierarchy

System.Object
VDS.RDF.Query.Expressions.PrimaryExpressionSubstituter
VDS.RDF.Query.Optimisation.VariableSubstitutionTransformer

Namespace: VDS.RDF.Query.Optimisation
Assembly: dotNetRDF (in dotNetRDF.dll) Version:

Syntax

public class VariableSubstitutionTransformer : PrimaryExpressionSubstituter, 
	IAlgebraOptimiser

Public Class VariableSubstitutionTransformer
	Inherits PrimaryExpressionSubstituter
	Implements IAlgebraOptimiser

The VariableSubstitutionTransformer type exposes the following members.

Constructors

	Name	Description
	VariableSubstitutionTransformer(String, String)	Create a transform that replaces one variable with another.
	VariableSubstitutionTransformer(String, INode)	Create a transform that replaces a variable with a constant.

Properties

	Name	Description
	CanReplaceObjects	Gets/Sets whethe the Transformer is allowed to replace objects.

Methods

	Name	Description
	Equals	Determines whether the specified object is equal to the current object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Serves as the default hash function. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	IsApplicable(SparqlQuery)	Returns false because this optimiser is never globally applicable.
	IsApplicable(SparqlUpdateCommandSet)	Returns false because this optimiser is never globally applicable.
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	Optimise	Attempts to do variable substitution within the given algebra.
	SubstitutePrimaryExpression	Tries to substitute variables within primary expressions. (Overrides PrimaryExpressionSubstituter.SubstitutePrimaryExpression(ISparqlExpression).)
	ToString	Returns a string that represents the current object. (Inherited from Object.)
	Transform	Transforms an expression into a form where primary expressions may be substituted. (Inherited from PrimaryExpressionSubstituter.)