XSLT, XPath and XQuery Functions

XSLT 2.0, XPath 2.0 and XQuery 1.0, share the same functions library.

Functions Reference

note

The default prefix for the function namespace is fn:
The URI of the function namespace is: http://www.w3.org/2005/xpath-functions

note

Functions are often called with the fn: prefix, such as fn:string(). However, since fn: is the default prefix of the namespace, the function names do not need to be prefixed when called.

Accessor Functions

Name	Description
`fn:node-name(node)`	Returns the node-name of the argument node
`fn:nilled(node)`	Returns a Boolean value indicating whether the argument node is nilled
`fn:data(item.item,...)`	Takes a sequence of items and returns a sequence of atomic values
`fn:base-uri()`	Returns the value of the base-uri property of the current node
`fn:base-uri(node)`	Returns the value of the base-uri property of the specified node
`fn:document-uri(node)`	Returns the value of the document-uri property for the specified node

Error and Trace Functions

Name	Description
`fn:error()` `fn:error(error)` `fn:error(error,description)` `fn:error(error,description,error-object)`	Example: `error(fn:QName('http://example.com/test', 'err:toohigh'), 'Error: Price is too high')` Result: Returns http://example.com/test#toohigh and the string "Error: Price is too high" to the external processing environment
`fn:trace(value,label)`	Used to debug queries

Functions on Numeric Values

Name	Description
`fn:number(arg)`	Returns the numeric value of the argument. The argument could be a boolean, string, or node-set Example: `number('100')` Result: 100
`fn:abs(num)`	Returns the absolute value of the argument Example: `abs(3.14)` Result: 3.14 Example: `abs(-3.14)` Result: 3.14
`fn:ceiling(num)`	Returns the smallest integer that is greater than the number argument Example: `ceiling(3.14)` Result: 4
`fn:floor(num)`	Returns the largest integer that is not greater than the number argument Example: `floor(3.14)` Result: 3
`fn:round(num)`	Rounds the number argument to the nearest integer Example: `round(3.14)` Result: 3
`fn:round-half-to-even()`	Rounds the number argument to the nearest integer even number Example: `round-half-to-even(0.5)` Result: 0 Example: `round-half-to-even(1.5)` Result: 2 Example: `round-half-to-even(2.5)` Result: 2

Functions on Strings

Name	Description
`fn:string(arg)`	Returns the string value of the argument. The argument could be a number, boolean, or node-set Example: `string(314)` Result: "314"
`fn:codepoints-to-string((int,int,...))`	Creates a string from a sequence of the Unicode Standard code points Example: `codepoints-to-string((84, 104, 233, 114, 232, 115, 101))` Result: 'Thérèse'
`fn:string-to-codepoints(string)`	Returns the sequence of the Unicode standard code points from a string Example: string-to-`codepoints("Thérèse")` Result: (84, 104, 233, 114, 232, 115, 101)
`fn:codepoint-equal(comp1,comp2)`	Returns true if the value of comp1 is equal to the value of comp2, according to the Unicode code point collation (http://www.w3.org/2005/02/xpath-functions/collation/codepoint), otherwise it returns false
`fn:compare(comp1,comp2)` `fn:compare(comp1,comp2,collation)`	Returns -1 if comp1 is less than comp2, 0 if comp1 is equal to comp2, or 1 if comp1 is greater than comp2 (according to the rules of the collation that is used) Example: `compare('ghi', 'ghi')` Result: 0
`fn:concat(string,string,...)`	Returns the concatenation of the strings Example: `concat('XPath ','is ','FUN!')` Result: 'XPath is FUN!'
`fn:string-join((string,string,...),sep)`	Returns a string created by concatenating the string arguments and using the sep argument as the separator Example: `string-join(('We', 'are', 'having', 'fun!'), ' ')` Result: ' We are having fun! ' Example: `string-join(('We', 'are', 'having', 'fun!'))` Result: 'Wearehavingfun!' Example: `string-join((), 'sep')` Result: ''
`fn:substring(string,start,len)` `fn:substring(string,start)`	Returns the substring from the start position to the specified length. Index of the first character is 1. If length is omitted it returns the substring from the start position to the end Example: `substring('Beatles',1,4)` Result: 'Beat' Example: `substring('Beatles',2)` Result: 'eatles'
`fn:string-length(string)` `fn:string-length()`	Returns the length of the specified string. If there is no string argument it returns the length of the string value of the current node Example: `string-length('Beatles')` Result: 7
`fn:normalize-space(string)` `fn:normalize-space()`	Removes leading and trailing spaces from the specified string, and replaces all internal sequences of white space with one and returns the result. If there is no string argument it does the same on the current node Example: `normalize-space(' The XML ')` Result: 'The XML'
`fn:normalize-unicode(string)` `fn:normalize-unicode(string, normalizationForm)`	Performs Unicode normalization to the string argument. The normalizationForm argument controls which normalization form is used, and hence which characters are replaced.
`fn:upper-case(string)`	Converts the string argument to upper-case Example: `upper-case('The XML')` Result: 'THE XML'
`fn:lower-case(string)`	Converts the string argument to lower-case Example: `lower-case('The XML')` Result: 'the xml'
`fn:translate(string1,string2,string3)`	Converts string1 by replacing the characters in string2 with the characters in string3 Example: `translate('12:30','30','45')` Result: '12:45' Example: translate('12:30','03','54') Result: '12:45' Example: `translate('12:30','0123','abcd')` Result: 'bc:da'
`fn:escape-uri(stringURI,esc-res)`	Applies the URI escaping rules to argument string that contains a URI Example: `escape-uri("http://example.com/test#car", true())` Result: "http%3A%2F%2Fexample.com%2Ftest#car" Example: `escape-uri("http://example.com/test#car", false())` Result: "http://example.com/test#car" Example: `escape-uri ("http://example.com/~bébé", false())` Result: "http://example.com/~b%C3%A9b%C3%A9"
`fn:contains(string1,string2)`	Returns true if string1 contains string2, otherwise it returns false Example: `contains('XML','XM')` Result: true
`fn:starts-with(string1,string2)`	Returns true if string1 starts with string2, otherwise it returns false Example: `starts-with('XML','X')` Result: true
`fn:ends-with(string1,string2)`	Returns true if string1 ends with string2, otherwise it returns false Example: `ends-with('XML','X')` Result: false
`fn:substring-before(string1,string2)`	Returns the start of string1 before string2 occurs in it Example: `substring-before('12/10','/')` Result: '12'
`fn:substring-after(string1,string2)`	Returns the rest of string1 after string2 is in it Example: `substring-after('12/10','/')` Result: '10'
`fn:matches(string,pattern)`	Returns true if the string argument matches the pattern, otherwise, it returns false Example: `matches("Merano", "ran")` Result: true
`fn:replace(string,pattern,replace)`	Returns a string that is created by replacing the given pattern with the replace argument Example: `replace("Bella Italia", "l", "")` Result: 'Bea Itaia' Example: `replace("Bella Italia", "l", "")` Result: 'Bea Itaia'
`fn:tokenize(string,pattern)`	Splits the argument string based on a pattern (that is regular expression) Example: `tokenize("XPath is fun", "\s+")` Result: ("XPath", "is", "fun")

Functions for anyURI

Name	Description
`fn:resolve-uri(relative,base)`	Takes a base URI (base) and a relative URI (relative) as arguments, and creates and returns an absolute URI. If base is not provided, the base URI of the static context is used.

Functions on Boolean Values

Name	Description
`fn:boolean(arg)`	Returns a boolean value for a number, string, or node-set
`fn:not(arg)`	The argument is first reduced to a boolean value by applying the `boolean()` function. Returns true if the boolean value is false, and false if the boolean value is true Example: `not(true())` Result: false
`fn:true()`	Returns the boolean value true Example: `true()` Result: true
`fn:false()`	Returns the boolean value false Example: `false()` Result: false

Functions on Durations, Dates and Times

Name	Description
`fn:dateTime(date,time)`	Converts the arguments to a date and a time
`fn:years-from-duration(datetimedur)`	Returns an integer that represents the years component in the canonical lexical representation of the value of the argument
`fn:months-from-duration(datetimedur)`	Returns an integer that represents the months component in the canonical lexical representation of the value of the argument
`fn:days-from-duration(datetimedur)`	Returns an integer that represents the days component in the canonical lexical representation of the value of the argument
`fn:hours-from-duration(datetimedur)`	Returns an integer that represents the hours component in the canonical lexical representation of the value of the argument
`fn:minutes-from-duration(datetimedur)`	Returns an integer that represents the minutes component in the canonical lexical representation of the value of the argument
`fn:seconds-from-duration(datetimedur)`	Returns a decimal that represents the seconds component in the canonical lexical representation of the value of the argument
`fn:year-from-dateTime(datetime)`	Returns an integer that represents the year component in the localized value of the argument Example: `year-from-dateTime(xs:dateTime("2005-01-10T12:30-04:10"))` Result: 2005
`fn:month-from-dateTime(datetime)`	Returns an integer that represents the month component in the localized value of the argument Example: `month-from-dateTime(xs:dateTime("2005-01-10T12:30-04:10"))` Result: 01
`fn:day-from-dateTime(datetime)`	Returns an integer that represents the day component in the localized value of the argument Example: `day-from-dateTime(xs:dateTime("2005-01-10T12:30-04:10"))` Result: 10
`fn:hours-from-dateTime(datetime)`	Returns an integer that represents the hours component in the localized value of the argument Example: `hours-from-dateTime(xs:dateTime("2005-01-10T12:30-04:10"))` Result: 12
`fn:minutes-from-dateTime(datetime)`	Returns an integer that represents the minutes component in the localized value of the argument Example: `minutes-from-dateTime(xs:dateTime("2005-01-10T12:30-04:10"))` Result: 30
`fn:seconds-from-dateTime(datetime)`	Returns a decimal that represents the seconds component in the localized value of the argument Example: `seconds-from-dateTime(xs:dateTime("2005-01-10T12:30:00-04:10"))` Result: 0
`fn:timezone-from-dateTime(datetime)`	Returns the time zone component of the argument if any
`fn:year-from-date(date)`	Returns an integer that represents the year in the localized value of the argument Example: `year-from-date(xs:date("2005-04-23"))` Result: 2005
`fn:month-from-date(date)`	Returns an integer that represents the month in the localized value of the argument Example: `month-from-date(xs:date("2005-04-23"))` Result: 4
`fn:day-from-date(date)`	Returns an integer that represents the day in the localized value of the argument Example: `day-from-date(xs:date("2005-04-23"))` Result: 23
`fn:timezone-from-date(date)`	Returns the time zone component of the argument if any
`fn:hours-from-time(time)`	Returns an integer that represents the hours component in the localized value of the argument Example: `hours-from-time(xs:time("10:22:00"))` Result: 10
`fn:minutes-from-time(time)`	Returns an integer that represents the minutes component in the localized value of the argument Example: `minutes-from-time(xs:time("10:22:00"))` Result: 22
`fn:seconds-from-time(time)`	Returns an integer that represents the seconds component in the localized value of the argument Example: `seconds-from-time(xs:time("10:22:00"))` Result: 0
`fn:timezone-from-time(time)`	Returns the time zone component of the argument if any
`fn:adjust-dateTime-to-timezone(datetime,timezone)`	If the timezone argument is empty, it returns a dateTime without a timezone. Otherwise, it returns a dateTime with a timezone
`fn:adjust-date-to-timezone(date,timezone)`	If the timezone argument is empty, it returns a date without a timezone. Otherwise, it returns a date with a timezone
`fn:adjust-time-to-timezone(time,timezone)`	If the timezone argument is empty, it returns a time without a timezone. Otherwise, it returns a time with a timezone

Name	Description
`fn:QName(paramURI,paramQName)`	Takes a namespace URI and a qualified (optionally prefixed) name as arguments, and constructs a QName value from them
`fn:local-name-from-QName(QName)`	Returns the local part of a QName
`fn:namespace-uri-from-QName(QName)`	Returns the namespace part of a QName
`fn:namespace-uri-for-prefix(prefix, element)`	Returns the namespace mapped to prefix, using the in-scope namespaces of the element. If prefix is a zero-length string or the empty sequence, the function returns the default namespace, if any.
`fn:in-scope-prefixes(element)`	Returns a sequence of prefixes (as strings) that are used in the in-scope namespaces for the element element
`fn:resolve-QName(QName, element)`	Resolves a QName based on the in-scope namespaces of an element. The QName argument is a string representing a qualified name. It can be prefixed or unprefixed. The element argument is the element whose in-scope namespaces are to be used to determine which namespace URI is mapped to the prefix.

Functions on Nodes

Name	Description
`fn:name()` `fn:name(nodeset)`	Returns the name of the current node or the first node in the specified node set
`fn:local-name()` `fn:local-name(nodeset)`	Returns the name of the current node or the first node in the specified node set - without the namespace prefix
`fn:namespace-uri()` `fn:namespace-uri(nodeset)`	Returns the namespace URI of the current node or the first node in the specified node set
`fn:lang(lang)`	Returns true if the language of the current node matches the language of the specified language Example: `Lang("en")` is true for `<p xml:lang="en">...</p>` Example: `Lang("de")` is false for `<p xml:lang="en">...</p>`
`fn:root()` `fn:root(node)`	Returns the root of the tree to which the current node or the specified belongs. This will usually be a document node

Functions on Sequences

General Functions on Sequences

Name	Description
`fn:index-of((item,item,...),searchitem)`	Returns the positions within the sequence of items that are equal to the searchitem argument Example: `index-of((15, 40, 25, 40, 10), 40)` Result: (2, 4) Example: `index-of(("a", "dog", "and", "a", "duck"), "a")` Result (1, 4) Example: `index-of((15, 40, 25, 40, 10), 18)` Result: ()
`fn:remove((item,item,...),position)`	Returns a new sequence constructed from the value of the item arguments - with the item specified by the position argument removed Example: `remove(("ab", "cd", "ef"), 0)` Result: ("ab", "cd", "ef") Example: `remove(("ab", "cd", "ef"), 1)` Result: ("cd", "ef") Example: `remove(("ab", "cd", "ef"), 4)` Result: ("ab", "cd", "ef")
`fn:empty(item,item,...)`	Returns true if the value of the arguments IS an empty sequence, otherwise it returns false Example: `empty(remove(("ab", "cd"), 1))` Result: false
`fn:exists(item,item,...)`	Returns true if the value of the arguments IS NOT an empty sequence, otherwise it returns false Example: `exists(remove(("ab"), 1))` Result: false
`fn:distinct-values((item,item,...),collation)`	Returns only distinct (different) values Example: `distinct-values((1, 2, 3, 1, 2))` Result: (1, 2, 3)
`fn:insert-before((item,item,...),pos,inserts)`	Returns a new sequence constructed from the value of the item arguments - with the value of the inserts argument inserted in the position specified by the pos argument Example: `insert-before(("ab", "cd"), 0, "gh")` Result: ("gh", "ab", "cd") Example: `insert-before(("ab", "cd"), 1, "gh")` Result: ("gh", "ab", "cd") Example: `insert-before(("ab", "cd"), 2, "gh")` Result: ("ab", "gh", "cd") Example: `insert-before(("ab", "cd"), 5, "gh")` Result: ("ab", "cd", "gh")
`fn:reverse((item,item,...))`	Returns the reversed order of the items specified Example: `reverse(("ab", "cd", "ef"))` Result: ("ef", "cd", "ab") Example: `reverse(("ab"))` Result: ("ab")
`fn:subsequence((item,item,...),start,len)`	Returns a sequence of items from the position specified by the start argument and continuing for the number of items specified by the len argument. The first item is located at position 1 Example: `subsequence(($item1, $item2, $item3,...), 3)` Result: ($item3, ...) Example: `subsequence(($item1, $item2, $item3, ...), 2, 2)` Result: ($item2, $item3)
`fn:unordered((item,item,...))`	Returns the items in an implementation dependent order

Functions That Test the Cardinality of Sequences

Name	Description
`fn:zero-or-one(item,item,...)`	Returns the argument if it contains zero or one items, otherwise it raises an error
`fn:one-or-more(item,item,...)`	Returns the argument if it contains one or more items, otherwise it raises an error
`fn:exactly-one(item,item,...)`	Returns the argument if it contains exactly one item, otherwise it raises an error

Equals, Union, Intersection and Except

Name	Description
`fn:deep-equal(param1,param2,collation)`	Returns true if param1 and param2 are deep-equal to each other, otherwise it returns false

Aggregate Functions

Name	Description
`fn:count((item,item,...))`	Returns the count of nodes
`fn:avg((arg,arg,...))`	Returns the average of the argument values Example: `avg((1,2,3))` Result: 2
`fn:max((arg,arg,...))`	Returns the argument that is greater than the others Example: `max((1,2,3))` Result: 3 Example: `max(('a', 'k'))` Result: 'k'
`fn:min((arg,arg,...))`	Returns the argument that is less than the others Example: `min((1,2,3))` Result: 1 Example: `min(('a', 'k'))` Result: 'a'
`fn:sum(arg,arg,...)`	Returns the sum of the numeric value of each node in the specified node-set

Functions that Generate Sequences

Name	Description
`fn:id((string,string,...),node)`	Returns a sequence of element nodes that have an ID value equal to the value of one or more of the values specified in the string argument
`fn:idref((string,string,...),node)`	Returns a sequence of element or attribute nodes that have an IDREF value equal to the value of one or more of the values specified in the string argument
`fn:doc(URI)`	Returns the document node of the resource found at the specified URI.
`fn:doc-available(URI)`	Returns true if the `doc()` function returns a document node, otherwise it returns false
`vfn:collection()` `fn:collection(string)`	Returns a collection. A collection at a certain URI can be loaded passing that URI as a string argument

Context Functions

Name	Description
`fn:position()`	Returns the index position of the node that is currently being processed Example: `//book[position()<=3]` Result: Selects the first three book elements
`fn:last()`	Returns the number of items in the processed node list Example: `//book[last()]` Result: Selects the last book element
`fn:current-dateTime()`	Returns the current dateTime (with timezone)
`fn:current-date()`	Returns the current date (with timezone)
`fn:current-time()`	Returns the current time (with timezone)
`fn:implicit-timezone()`	Returns the value of the implicit timezone
`fn:default-collation()`	Returns the value of the default collation
`fn:static-base-uri()`	Returns the value of the base-uri

XSLT Functions

In addition, there are the following built-in XSLT functions.

These are discussed in XSLT Built-in Functions Chapter.

XSLT, XPath and XQuery Functions

Functions Reference​

Accessor Functions​

Error and Trace Functions​

Functions on Numeric Values​

Functions on Strings​

Functions for anyURI​

Functions on Boolean Values​

Functions on Durations, Dates and Times​

Functions Related to QNames​

Functions on Nodes​

Functions on Sequences​

General Functions on Sequences​

Functions That Test the Cardinality of Sequences​

Equals, Union, Intersection and Except​

Aggregate Functions​

Functions that Generate Sequences​

Context Functions​

XSLT Functions​

Table of Contents