Package net.sf.saxon.functions.registry

Interface FunctionDefinition

All Known Implementing Classes:
BuiltInFunctionSet.Entry, MemoFunction, StreamableUserFunction, UserFunction, XQueryFunction
public interface FunctionDefinition
A FunctionDefinition represents the declaration of a user-defined function in XQuery or XSLT; in 4.0 a function definition has an arity range. The minimum arity is the number of mandatory parameters, the maximum arity is the number of optional plus mandatory parameters; optional parameters have a default value which is supplied as an expression.

  • Method Details

    • getFunctionName

      StructuredQName getFunctionName()
      Get the name of the function
      Returns:
      the function name

    • getNumberOfParameters

      int getNumberOfParameters()
      Get the number of declared parameters (the upper bound of the arity range)
      Returns:
      the number of declared parameters

    • getMinimumArity

      int getMinimumArity()
      Get the number of mandatory arguments (the lower bound of the arity range)
      Returns:
      the number of mandatory arguments

    • getParameterName

      StructuredQName getParameterName(int i)
      Get the name (keyword) of the Nth parameter
      Parameters:
      i - the position of the required parameter
      Returns:
      the expression for computing the value of the Nth parameter

    • getDefaultValueExpression

      Expression getDefaultValueExpression(int i)
      Get the default value expression of the Nth parameter, if any
      Parameters:
      i - the position of the required parameter
      Returns:
      the expression for computing the value of the Nth parameter, or null if there is none

    • getPositionOfParameter

      int getPositionOfParameter(StructuredQName name)
      Get the position in the parameter list of a given parameter name
      Parameters:
      name - the name of the required parameter
      Returns:
      the position of the parameter in the parameter list, or -1 if absent