net.sf.saxon.om

Interface Function

All Superinterfaces:

Callable, GroundedValue<Function>, Item<Function>, java.lang.Iterable<Function>, Sequence<Function>

All Known Subinterfaces:

ArrayItem, MapItem

All Known Implementing Classes:

Abs, AbstractArrayItem, AbstractFunction, AccessorFn, AccessorFn.DayFromDate, AccessorFn.DayFromDateTime, AccessorFn.DaysFromDuration, AccessorFn.HoursFromDateTime, AccessorFn.HoursFromDuration, AccessorFn.HoursFromTime, AccessorFn.LocalNameFromQName, AccessorFn.MinutesFromDateTime, AccessorFn.MinutesFromDuration, AccessorFn.MinutesFromTime, AccessorFn.MonthFromDate, AccessorFn.MonthFromDateTime, AccessorFn.MonthsFromDuration, AccessorFn.NamespaceUriFromQName, AccessorFn.PrefixFromQName, AccessorFn.SecondsFromDateTime, AccessorFn.SecondsFromDuration, AccessorFn.SecondsFromTime, AccessorFn.TimezoneFromDate, AccessorFn.TimezoneFromDateTime, AccessorFn.TimezoneFromTime, AccessorFn.YearFromDate, AccessorFn.YearFromDateTime, AccessorFn.YearsFromDuration, AccumulatorFn, AccumulatorFn.AccumulatorAfter, AccumulatorFn.AccumulatorBefore, Adjust_1, Adjust_2, Aggregate, AnalyzeStringFn, ApplyFn, ArrayFunctionSet.ArrayAppend, ArrayFunctionSet.ArrayFilter, ArrayFunctionSet.ArrayFlatten, ArrayFunctionSet.ArrayFoldLeft, ArrayFunctionSet.ArrayFoldRight, ArrayFunctionSet.ArrayForEach, ArrayFunctionSet.ArrayForEachPair, ArrayFunctionSet.ArrayFromSequence, ArrayFunctionSet.ArrayGet, ArrayFunctionSet.ArrayHead, ArrayFunctionSet.ArrayInsertBefore, ArrayFunctionSet.ArrayJoin, ArrayFunctionSet.ArrayPut, ArrayFunctionSet.ArrayRemove, ArrayFunctionSet.ArrayReverse, ArrayFunctionSet.ArraySize, ArrayFunctionSet.ArraySubarray, ArrayFunctionSet.ArrayTail, ArrayFunctionSet.ArrayToSequence, ArrayMember, ArraySort, AtomicConstructorFunction, AvailableEnvironmentVariables, AvailableSystemProperties, Average, BaseUri_1, BooleanFn, CallableFunction, Ceiling, CodepointEqual, CodepointsToString, CoercedFunction, CollatingFunctionFixed, CollatingFunctionFree, CollationKeyFn, CollectionFn, Compare, CompileQuery, CompileStylesheet, CompileXPath, Concat, ConstantFunction, ConstantFunction.False, ConstantFunction.True, Contains, ContainsToken, ContextAccessorFunction, ContextItemAccessorFunction, ContextItemAccessorFunction.Number_0, ContextItemAccessorFunction.StringAccessor, CopyOfFn, Count, Current, CurrentGroup, CurrentGroupingKey, CurrentMergeGroup, CurrentMergeKey, CurrentOutputUri, CurriedFunction, Data_1, DateTimeConstructor, DecimalDivide, DeepEqual, DeepEqual, DelegatingArrayItem, DelegatingMapItem, DictionaryMap, DistinctValues, Doc, Doc_2, DocAvailable, DocumentFn, DocumentUri_1, DynamicContextAccessor, DynamicContextAccessor.CurrentDate, DynamicContextAccessor.CurrentDateTime, DynamicContextAccessor.CurrentTime, DynamicContextAccessor.DefaultLanguage, DynamicContextAccessor.ImplicitTimezone, ElementAvailable, Empty, EncodeForUri, EndsWith, EnvironmentVariable, Error, EscapeHtmlUri, Eval, Evaluate, EvaluateNode, Exists, EXPathFileFunctionSet.BaseDir, ExpressionFn, ExsltCommonFunctionSet.NodeSetFn, ExsltCommonFunctionSet.ObjectTypeFn, FilterFn, Floor, FoldingFunction, FoldLeftFn, FoldRightFn, ForEachFn, ForEachPairFn, FormatDate, FormatInteger, FormatNumber, FunctionAnnotations, FunctionArity, FunctionAvailable, FunctionLookup, FunctionName, GenerateId_1, GroupStarting, HasChildren_1, HashTrieMap, HeadFn, HighestOrLowest, Idref, ImmutableArrayItem, Index, IndexOf, Innermost, InScopePrefixes, InsertBefore, IriToUri, IXSLFunctionSet.Call, IXSLFunctionSet.Eval, IXSLFunctionSet.ScheduleActionFn, IXSLFunctionSet.Source, IXSLFunctionSet.Stub, JsonDoc, JsonToXMLFn, KeyFn, KeyMap, Lang, LastModified, Leading, ListCastableFunction, ListConstructorFunction, LoadXqueryModule, LocalName_1, LowerCase, MapCreate, MapFunctionSet.MapContains, MapFunctionSet.MapEntry, MapFunctionSet.MapFind, MapFunctionSet.MapForEach, MapFunctionSet.MapGet, MapFunctionSet.MapKeys, MapFunctionSet.MapMerge, MapFunctionSet.MapPut, MapFunctionSet.MapRemove, MapFunctionSet.MapSize, MapSearch, MapUntypedContains, Matches, MathFunctionSet.AcosFn, MathFunctionSet.AsinFn, MathFunctionSet.Atan2Fn, MathFunctionSet.AtanFn, MathFunctionSet.CosFn, MathFunctionSet.Exp10Fn, MathFunctionSet.ExpFn, MathFunctionSet.Log10Fn, MathFunctionSet.LogFn, MathFunctionSet.PiFn, MathFunctionSet.PowFn, MathFunctionSet.SinFn, MathFunctionSet.SqrtFn, MathFunctionSet.TanFn, MemoFunction, MessageCount, Minimax, Minimax.Max, Minimax.Min, Name_1, NamespaceForPrefix, NamespaceUri_1, Nilled_1, NodeName_1, NormalizeSpace_1, NormalizeUnicode, NotFn, Number_1, ObjectMap, OriginalFunction, Outermost, Parse, ParseHtml, ParseIetfDate, ParseJsonFn, ParseXml, ParseXmlFragment, ParseXPath, Path_1, PedigreeArrayItem, PedigreeFn, PedigreeMapItem, PositionAndLast, PositionAndLast.Last, PositionAndLast.Position, Put, QNameFn, QueryFn, RandomNumberGenerator, RangeKey, RegexFunction, RegexFunctionSansFlags, RegexGroup, Remove, Replace, ResolveQName, ResolveURI, Reverse, Root_1, Round, RoundHalfToEven, ScalarSystemFunction, SchemaFn, SendMail, Serialize, Serialize, SimpleArrayItem, SingleEntryMap, SnapshotFn, Sort_1, Sort_2, Sort_3, SQLConnectFn, SQLDeleteFn, SQLExecuteFn, SQLInsertFn, SQLPreparedQueryFn, SQLPreparedStatementFn, SQLQueryFn, SQLUpdateFn, StartsWith, StaticBaseUri, StaticContextAccessor, StaticContextAccessor.DefaultCollation, StaticContextAccessor.StaticBaseUri, StreamableUserFunction, StreamAvailable, StreamFn, String_1, StringJoin, StringLength_1, StringToCodepoints, Subsequence_2, Subsequence_3, Substring, SubstringAfter, SubstringBefore, Sum, SuperId, SuperId.ElementWithId, SuperId.Id, SystemFunction, SystemFunctionWithBoundContextItem, SystemProperty, TailFn, TimestampFn, Tokenize_1, Tokenize_3, Trace, TransformFn, TransformFn, Translate, TreatFn, TreatFn.ExactlyOne, TreatFn.OneOrMore, TreatFn.ZeroOrOne, TypeAvailable, UnionCastableFunction, UnionConstructorFunction, Unordered, UnparsedEntity, UnparsedEntity.UnparsedEntityPublicId, UnparsedEntity.UnparsedEntityUri, UnparsedText, UnparsedTextAvailable, UnparsedTextFunction, UnparsedTextLines, UnresolvedXQueryFunctionItem, UpperCase, UriCollection, UserFunction, UserFunctionReference.BoundUserFunction, ValidateFn, VendorFunctionSetHE.DynamicErrorInfoFn, VendorFunctionSetHE.HasLocalNamespaces, VendorFunctionSetHE.HasUniformNamespaces, VendorFunctionSetHE.IsWholeNumberFn, WithPedigree, XMLToJsonFn

public interface Function
extends Item<Function>, Callable, GroundedValue<Function>

XDM 3.0 introduces a third kind of item, beyond nodes and atomic values: the function. Functions implement this interface.

Method Summary

Modifier and Type	Method and Description
static Sequence<?>[]	argumentArray(Sequence<?>... args)
Sequence<?>	call(XPathContext context, Sequence[] args) Invoke the function
boolean	deepEquals(Function other, XPathContext context, AtomicComparer comparer, int flags) Test whether this FunctionItem is deep-equal to another function item, under the rules of the deep-equal function
void	export(ExpressionPresenter out) Output information about this function item to the diagnostic explain() output
AnnotationList	getAnnotations() Get the function annotations (as defined in XQuery).
int	getArity() Get the arity of the function
java.lang.String	getDescription() Get a description of this function for use in error messages.
FunctionItemType	getFunctionItemType() Get the item type of the function item
StructuredQName	getFunctionName() Get the name of the function, or null if it is anonymous
default Genre	getGenre() Get the genre of this item
OperandRole[]	getOperandRoles() Get the roles of the arguments, for the purposes of streaming
boolean	isArray() Ask whether this function item is an array
boolean	isMap() Ask whether this function item is a map
boolean	isTrustedResultType() Check that result type is of the trusted system functions to return a result of the correct type
XPathContext	makeNewContext(XPathContext callingContext, ContextOriginator originator) Prepare an XPathContext object for evaluating the function
default java.lang.String	toShortString() Provide a short string showing the contents of the item, suitable for use in error messages

Methods inherited from interface net.sf.saxon.om.Item

atomize, getLength, getStringValue, getStringValueCS, head, isStreamed, itemAt, iterate, iterator, reduce, subsequence, toGroundedValue

Methods inherited from interface net.sf.saxon.om.GroundedValue

asIterable, effectiveBooleanValue, materialize

Methods inherited from interface net.sf.saxon.om.Sequence

makeRepeatable

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

isMap

boolean isMap()

Ask whether this function item is a map

Returns:

true if this function item is a map, otherwise false

isArray

boolean isArray()

Ask whether this function item is an array

Returns:

true if this function item is an array, otherwise false

getFunctionItemType

FunctionItemType getFunctionItemType()

Get the item type of the function item

Returns:

the function item's type

getFunctionName

StructuredQName getFunctionName()

Get the name of the function, or null if it is anonymous

Returns:

the function name, or null for an anonymous inline function

getArity

int getArity()

Get the arity of the function

Returns:

the number of arguments in the function signature

getOperandRoles

OperandRole[] getOperandRoles()

Get the roles of the arguments, for the purposes of streaming

Returns:

an array of OperandRole objects, one for each argument

getAnnotations

AnnotationList getAnnotations()

Get the function annotations (as defined in XQuery). Returns an empty list if there are no function annotations.

Returns:

the function annotations

makeNewContext

XPathContext makeNewContext(XPathContext callingContext,
                            ContextOriginator originator)

Prepare an XPathContext object for evaluating the function

Parameters:

callingContext - the XPathContext of the function calling expression

originator - identifies the location of the caller for diagnostics

Returns:

a suitable context for evaluating the function (which may or may not be the same as the caller's context)

call

Sequence<?> call(XPathContext context,
                 Sequence[] args)
          throws XPathException

Invoke the function

Specified by:

call in interface Callable

Parameters:

context - the XPath dynamic evaluation context

args - the actual arguments to be supplied

Returns:

the result of invoking the function

Throws:

XPathException - if a dynamic error occurs within the function

deepEquals

boolean deepEquals(Function other,
                   XPathContext context,
                   AtomicComparer comparer,
                   int flags)
            throws XPathException

Test whether this FunctionItem is deep-equal to another function item, under the rules of the deep-equal function

Parameters:

other - the other function item

context - the dynamic evaluation context

comparer - the object to perform the comparison

flags - options for how the comparison is performed

Returns:

true if the two function items are deep-equal

Throws:

XPathException - if the comparison cannot be performed

getDescription

java.lang.String getDescription()

Get a description of this function for use in error messages. For named functions, the description is the function name (as a lexical QName). For others, it might be, for example, "inline function", or "partially-applied ends-with function".

Returns:

a description of the function for use in error messages

export

void export(ExpressionPresenter out)
     throws XPathException

Output information about this function item to the diagnostic explain() output

Throws:

XPathException

isTrustedResultType

boolean isTrustedResultType()

Check that result type is of the trusted system functions to return a result of the correct type

toShortString

default java.lang.String toShortString()

Provide a short string showing the contents of the item, suitable for use in error messages

Specified by:

toShortString in interface GroundedValue<Function>

Specified by:

toShortString in interface Item<Function>

Returns:

a depiction of the item suitable for use in error messages

getGenre

default Genre getGenre()

Get the genre of this item

Specified by:

getGenre in interface Item<Function>

Returns:

the genre: specifically, Genre.FUNCTION. Overridden for maps and arrays.

argumentArray

@SafeVarargs
static Sequence<?>[] argumentArray(Sequence<?>... args)