# Package com.icl.saxon.expr

- Interface Summary
  Interface | Description
  --- | ---
  LastPositionFinder | A LastPositionFinder is an object used by the Context to locate the last position in the context node list.
  StaticContext | A StaticContext contains the information needed while an expression or pattern is being parsed.

- Class Summary
  Class | Description
  --- | ---
  AttributeValueTemplate | This class represents an attribute value template.
  BooleanValue | A boolean XPath value
  ContextNodeExpression | This class represents the expression ".", which always returns the context node.
  DifferenceEnumeration | An enumeration representing a nodeset that is an intersection of two other NodeSets.
  DistinctEnumeration | An enumeration returning the distinct nodes from a supplied nodeset
  EmptyNodeSet | A node-set value no nodes
  ErrorExpression | Error expression: this expression is generated when the supplied expression cannot be parsed, and the containing element enables forwards-compatible processing.
  Expression | This class serves two purposes: it is an abstract superclass for different kinds of XPath expression, and it contains a static method to invoke the expression parser
  ExpressionParser | Parser for XSL expressions and patterns.
  FilterEnumerator | A FilterEnumerator filters an input NodeEnumeration using a filter expression.
  FragmentValue | This class represents a Value of type result tree fragment.
  Function | Abstract superclass for system-defined and user-defined functions
  FunctionProxy | This class acts as a proxy for an extension function defined as a method in a user-defined class
  IntersectionEnumeration | An enumeration representing a nodeset that is an intersection of two other NodeSets.
  IsLastExpression | position()=last() expression
  LookaheadEnumerator | A LookaheadEnumerator passes the nodes from a base enumerator throgh unchanged.
  NodeListExpression | A NodeListExpression is an expression denoting a set of nodes sorted in document order.
  NodeSetComparison | NodeSetComparison: A Relational Expression that compares a node-set with a string or numeric value for equals, not-equals, greater-than or less-than.
  NodeSetExpression | A NodeSetExpression is any expression denoting a set of nodes.
  NodeSetExtent | A node-set value implemented extensionally.
  NodeSetIntent | A node-set value implemented intensionally.
  NodeSetValue | A node-set value.
  NumericValue | A numeric (floating point) value
  ObjectValue | An XPath value that encapsulates a Java object.
  ParentNodeExpression | Class ParentNodeExpression represents the XPath expression ".." or "parent::node()"
  PathExpression | An expression that establishes a set of nodes by following relationships between nodes in the document.
  RootExpression | An expression whose value is always a set of nodes containing a single node, the document root.
  SingletonComparison | Singleton Comparison: A Relational Expression that compares a singleton node-set with a string or numeric value for equals, not-equals, greater-than or less-than.
  SingletonExpression | A node set expression that will always return zero or one nodes
  SingletonNodeSet | A node-set value containing zero or one nodes
  SortedSelection | A NodeSetExpression that retrieves nodes in order according to a specified sort key.
  SortKeyEnumeration | A SortKeyEnumeration is NodeEnumeration that delivers the nodes sorted according to a specified sort key.
  StandaloneContext | A StandaloneContext provides a context for parsing an expression or pattern appearing in a context other than a stylesheet.
  Step | A step in a path expression
  StringValue | A string value
  StyleSheetFunctionCall | This class represents a call to a function defined in the stylesheet
  TextFragmentValue | This class represents a Value of type result tree fragment, specifically, an RTF whose root owns a single text node.
  UnionEnumeration | An enumeration representing a nodeset that is a union of two other NodeSets.
  Value | A value is the result of an expression but it is also an expression in its own right
  VariableReference | Variable reference: a reference to an XSL variable

- Exception Summary
  Exception | Description
  --- | ---
  XPathException | XPathException is used to indicate an error in an XPath expression.