net.sf.saxon.expr

Class PromoteToDouble

public class PromoteToDouble extends NumericPromoter

Expression that performs numeric promotion to xs:double

Constructor Summary
	PromoteToDouble(Expression exp)

Method Summary
Expression	copy() Copy an expression.
ItemType	getItemType(TypeHierarchy th) Determine the data type of the items returned by the expression, if possible
protected AtomicValue	promote(AtomicValue value, XPathContext context) Perform the promotion

Constructor Detail

public PromoteToDouble(Expression exp)

public Expression copy()

Copy an expression. This makes a deep copy.

Returns: the copy of the original expression

public ItemType getItemType(TypeHierarchy th)

Determine the data type of the items returned by the expression, if possible

Parameters: th the type hierarchy cache

Returns: a value such as Type.STRING, Type.BOOLEAN, Type.NUMBER, Type.NODE, or Type.ITEM (meaning not known in advance)

protected AtomicValue promote(AtomicValue value, XPathContext context)

Perform the promotion

Parameters: value the numeric or untyped atomic value to be promoted context the XPath dynamic evaluation context

Returns: the value that results from the promotion