Class Number_1

All Implemented Interfaces:
Callable, FunctionItem, GroundedValue, Item, Sequence

public class Number_1 extends ScalarSystemFunction
Implements the XPath fn:number() function when called with one argument. Note: this function accepts the value "+INF" whether or not XSD 1.1 is enabled.
  • Constructor Details

    • Number_1

      public Number_1()
  • Method Details

    • evaluate

      public AtomicValue evaluate(Item arg, XPathContext context) throws XPathException
      Description copied from class: ScalarSystemFunction
      Abstract method that must be supplied in subclasses to perform the evaluation
      Specified by:
      evaluate in class ScalarSystemFunction
      Parameters:
      arg - the supplied argument
      context - the dynamic context
      Returns:
      the result of the evaluation
      Throws:
      XPathException - if a dynamic error occurs
    • resultWhenEmpty

      public DoubleValue resultWhenEmpty()
      Description copied from class: ScalarSystemFunction
      Method that may be supplied in subclasses, to indicate the result that is returned when an empty sequence is supplied as the argument value. The default is to return the empty sequence
      Overrides:
      resultWhenEmpty in class ScalarSystemFunction
      Returns:
      the result of evaluation when the supplied argument is an empty sequence
    • typeCheckCaller

      public Expression typeCheckCaller(FunctionCall caller, ExpressionVisitor visitor, ContextItemStaticInfo contextInfo)
      Type-check a calling expression.
      Overrides:
      typeCheckCaller in class SystemFunction
      Parameters:
      caller - the function call expression calling this function
      visitor - the expression visitor
      contextInfo - static context information relating to the call
      Returns:
      a type-checked replacement for the supplied function call
    • toNumber

      public static DoubleValue toNumber(AtomicValue arg0)
      The actual implementation logic
      Parameters:
      arg0 - the atomic value to be converted
      Returns:
      the result of the conversion
    • convert

      public static DoubleValue convert(AtomicValue value, Configuration config)
      Static method to perform the same conversion as the number() function. This is different from the convert(Type.DOUBLE) in that it produces NaN rather than an error for non-numeric operands.
      Parameters:
      value - the value to be converted
      config - the Saxon configuration
      Returns:
      the result of the conversion
    • getElaborator

      public Elaborator getElaborator()
      Make an elaborator for a system function call on this function
      Overrides:
      getElaborator in class SystemFunction
      Returns:
      a suitable elaborator; or null if no custom elaborator is available