net.sf.saxon.functions

Class StandardFunction.Entry

java.lang.Object

net.sf.saxon.functions.StandardFunction.Entry

All Implemented Interfaces:

Serializable

Enclosing class:

StandardFunction

public static class StandardFunction.Entry
extends Object
implements Serializable

An entry in the table describing the properties of a function

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
int	applicability Flags indicating which host languages the function is applicable to
SequenceType[]	argumentTypes An array holding the types of the arguments to the function
int	cardinality The cardinality of the result of the function
Class	implementationClass The class containing the implementation of this function (always a subclass of SystemFunction)
ItemType	itemType The item type of the result of the function
int	maxArguments The maximum number of arguments permitted
int	minArguments The minimum number of arguments required
String	name The name of the function: a local name in the case of functions in the standard library, or a name with the conventional prefix "saxon:" in the case of Saxon extension functions
int	opcode Some classes support more than one function.
int	properties Any additional properties.
Sequence[]	resultIfEmpty An array holding, for each declared argument, the value that is to be returned if an empty sequence as the value of this argument allows the result to be determined irrespective of the values of the other arguments; null if there is no such calculation possible
OperandUsage[]	usage The syntactic context of each argument for the purposes of streamability analysis

Constructor Summary

Constructors

Constructor and Description
StandardFunction.Entry()

Method Summary

Methods

Modifier and Type	Method and Description
StandardFunction.Entry	arg(int a, ItemType type, int options, Sequence resultIfEmpty) Add information to a function entry about the argument types of the function

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

name

public String name

The name of the function: a local name in the case of functions in the standard library, or a name with the conventional prefix "saxon:" in the case of Saxon extension functions

implementationClass

public Class implementationClass

The class containing the implementation of this function (always a subclass of SystemFunction)

opcode

public int opcode

Some classes support more than one function. In these cases the particular function is defined by an integer opcode, whose meaning is local to the implementation class.

minArguments

public int minArguments

The minimum number of arguments required

maxArguments

public int maxArguments

The maximum number of arguments permitted

itemType

public ItemType itemType

The item type of the result of the function

cardinality

public int cardinality

The cardinality of the result of the function

applicability

public int applicability

Flags indicating which host languages the function is applicable to

usage

public OperandUsage[] usage

The syntactic context of each argument for the purposes of streamability analysis

argumentTypes

public SequenceType[] argumentTypes

An array holding the types of the arguments to the function

resultIfEmpty

public Sequence[] resultIfEmpty

An array holding, for each declared argument, the value that is to be returned if an empty sequence as the value of this argument allows the result to be determined irrespective of the values of the other arguments; null if there is no such calculation possible

properties

public int properties

Any additional properties. Currently one bit is defined: SAME_AS_FIRST_ARGUMENT indicates that the result type is the same as the type of the first argument

Constructor Detail

StandardFunction.Entry

public StandardFunction.Entry()

Method Detail

arg

public StandardFunction.Entry arg(int a,
                         ItemType type,
                         int options,
                         Sequence resultIfEmpty)

Add information to a function entry about the argument types of the function

Parameters:

a - the position of the argument, counting from zero

type - the item type of the argument

options - the cardinality and usage of the argument

resultIfEmpty - the value returned by the function if an empty sequence appears as the value of this argument, in the case when this result is unaffected by any other arguments. Supply null if this does not apply.

Returns:

this entry (to allow chaining)