[16] [[XPath]] には元々の [[XPath 1.0]] の他に大きな改訂を経た
[DFN[XPath 2.0]] がありました。更に小改訂を加えた
[DFN[XPath 3.0]] と [DFN[XPath 3.1]] がありました。

* データモデル

[79] [[XDM]] を採用していました。

* 応用

[17] [[XSLT 2.0]] は [[XPath 2.0]] を採用しています。

[4]
[[WSDM-MUWS]] では [[XPath 1.0]] または [[XPath 2.0]]
が利用できます。

[15] [CITE@en-US[Basic XML Schema Patterns for Databinding Version 1.0]] ([TIME[2009-05-05 01:07:15 +09:00]] 版) <http://www.w3.org/TR/2009/NOTE-xmlschema-patterns-20090505/#patterns-xpath>、
[CITE@en-US[Advanced XML Schema Patterns for Databinding Version 1.0]] ([TIME[2009-05-05 01:07:15 +09:00]] 版) <http://www.w3.org/TR/2009/NOTE-xmlschema-patterns-advanced-20090505/#patterns-xpath>

[36] [[STXPath]] は [[XPath 2.0]] の変種です。

[80] 
[[XPL]] は [[XPath 2.0]] (または [[XPath 1.0]]) を採用しています。

* 関連

[20] [[XPath 1.0]] では [[XPointer]] での利用が主要な応用の1つとして想定されていましたが、
[[XPath 2.0]] ではそうではないようです。 [[XPointer]] 用の [[XPointer scheme]]
として [CODE(XPointerScheme)@en[[[xpath2()]]]] が定義されてはいます。

** XPath 1.0 との関係

[18] [[XPath 2.0]] は [[XPath 1.0]] の改訂版ですが、言語仕様が大幅に改訂されています。
特に、 [[XPath 1.0]] は[[弱い型付け]]の[[言語]]でしたが、 [[XPath 2.0]] は[[強い型付け]]の[[言語]]となっています。

[21] [[DOM XPath]] 仕様は [[XPath 1.0]] にのみ対応しています。現時点で [[XPath 2.0]]
に対応させる動きはないようです。

** XQuery 1.0 との関係

[19] [[XPath 2.0]] は [[XQuery 1.0]] と協同して開発されました。両者は[[構文]]や[[意味論]]において基礎的な部分が共通しています。



* 歴史

[1]
[CITE[XQuery 1.0 and XPath 2.0 Data Model]] <http://www.w3.org/2004/07/data-model-issues.html>
([[名無しさん]])

[2]
[CITE[XQuery 1.0 and XPath 2.0 Data Model]] <http://www.w3.org/2004/10/data-model-issues.html>
([[名無しさん]])

[3]
[CITE[Data Model Last Call Comments]] <http://www.w3.org/XML/2003/05/xpath-datamodel-issues/>

[5]
[CITE@EN[XML Path Language (XPath) 2.0]] ([CODE[2007-01-19 08:23:20 +09:00]] 版) <http://www.w3.org/TR/2007/REC-xpath20-20070123/>
([[名無しさん]] [WEAK[2007-01-26 17:14:05 +00:00]])

[6]
[CITE@EN[XQuery 1.0 and XPath 2.0 Functions and Operators]] ([CODE[2007-01-19 07:02:42 +09:00]] 版) <http://www.w3.org/TR/2007/REC-xpath-functions-20070123/>
([[名無しさん]] [WEAK[2007-01-27 03:27:39 +00:00]])

[7]
[CITE@en[XQuery 1.0 and XPath 2.0 Data Model (XDM)]] ([CODE[2007-01-23 07:26:51 +09:00]] 版) <http://www.w3.org/TR/2007/REC-xpath-datamodel-20070123/>
([[名無しさん]] [WEAK[2007-01-27 04:58:33 +00:00]])

[8]
[CITE@EN[XQuery 1.0 and XPath 2.0 Formal Semantics]] ([CODE[2007-01-19 07:16:26 +09:00]] 版) <http://www.w3.org/TR/2007/REC-xquery-semantics-20070123/>
([[名無しさん]] [WEAK[2007-01-27 05:39:24 +00:00]])

[9]
[CITE@EN[XQuery 1.0 and XPath 2.0 Full-Text 1.0]] ([CODE[2007-05-17 06:07:03 +09:00]] 版) <http://www.w3.org/TR/2007/WD-xpath-full-text-10-20070518/>
([[名無しさん]] [WEAK[2007-05-28 23:34:27 +00:00]])

[10]
[CITE@EN[XQuery 1.0 and XPath 2.0 Full-Text 1.0 Requirements]] ([CODE[2007-05-19 03:59:30 +09:00]] 版) <http://www.w3.org/TR/2007/WD-xpath-full-text-10-requirements-20070518/>
([[名無しさん]] [WEAK[2007-05-28 23:35:16 +00:00]])


[11]
[CITE@EN[XQuery 1.0 and XPath 2.0 Full-Text 1.0 Use Cases]] ([TIME[2007-05-19 01:02:19 +09:00]] 版) <http://www.w3.org/TR/2007/WD-xpath-full-text-10-use-cases-20070518/>
([[名無しさん]] [WEAK[2007-05-28 23:35:58 +00:00]])

[12] [CITE@EN[XML Path Language (XPath) 2.0 (Second Edition)]] ([TIME[2009-04-21 23:42:37 +09:00]] 版) <http://www.w3.org/TR/2009/PER-xpath20-20090421/>

[13] [CITE@EN[XQuery 1.0 and XPath 2.0 Formal Semantics (Second Edition)]] ([TIME[2009-04-21 10:49:07 +09:00]] 版) <http://www.w3.org/TR/2009/PER-xquery-semantics-20090421/>

[14] [CITE@EN[XQuery 1.0 and XPath 2.0 Functions and Operators (Second Edition)]] ([TIME[2009-04-18 10:18:14 +09:00]] 版) <http://www.w3.org/TR/2009/PER-xpath-functions-20090421/>


[22] [CITE[XProc: An XML Pipeline Language]]
([TIME[2010-05-11 22:38:07 +09:00]] 版)
<http://www.w3.org/TR/2010/REC-xproc-20100511/#xpath-context>

[23] [CITE@en[XSLT 2.0 and XQuery 1.0 Serialization (Second Edition)]]
( ([TIME[2010-12-17 00:08:20 +09:00]] 版))
<http://www.w3.org/TR/2010/REC-xslt-xquery-serialization-20101214/#xslt20>

[24] [CITE@EN[XML Path Language (XPath) 2.0 (Second Edition)]]
( ([TIME[2011-01-05 01:25:51 +09:00]] 版))
<http://www.w3.org/TR/2010/REC-xpath20-20101214/>

[25] [CITE@en[Web Services Fragment (WS-Fragment)]]
( ([TIME[2011-12-13 17:58:12 +09:00]] 版))
<http://www.w3.org/TR/2011/REC-ws-fragment-20111213/#XPath20>

[26] [CITE@en[Web Services Eventing (WS-Eventing)]]
( ([TIME[2011-12-13 21:57:27 +09:00]] 版))
<http://www.w3.org/TR/2011/REC-ws-eventing-20111213/#Dialect>

[27] [CITE@en[Web Services Enumeration (WS-Enumeration)]]
( ([TIME[2011-12-13 20:20:29 +09:00]] 版))
<http://www.w3.org/TR/2011/REC-ws-enumeration-20111213/#Dialect>

[28] [CITE@EN[W3C XML Schema Definition Language (XSD) 1.1 Part 2: Datatypes]]
( ([TIME[2012-04-05 06:34:51 +09:00]] 版))
<http://www.w3.org/TR/2012/REC-xmlschema11-2-20120405/#xr-assertions>

[29] [CITE@EN[W3C XML Schema Definition Language (XSD) 1.1 Part 1: Structures]]
( ([TIME[2012-04-05 06:34:07 +09:00]] 版))
<http://www.w3.org/TR/2012/REC-xmlschema11-1-20120405/#Constraint_Summary>

[30] [CITE@EN[W3C XML Schema Definition Language (XSD) 1.1 Part 1: Structures]]
( ([TIME[2012-04-05 06:34:07 +09:00]] 版))
<http://www.w3.org/TR/2012/REC-xmlschema11-1-20120405/#icd-selector>

[31] [CITE@EN[W3C XML Schema Definition Language (XSD) 1.1 Part 1: Structures]]
( ([TIME[2012-04-05 06:34:07 +09:00]] 版))
<http://www.w3.org/TR/2012/REC-xmlschema11-1-20120405/#sec-c-selector-xpath>

[32] [CITE[RIF Combination with XML data (Second Edition)]]
( ([TIME[2013-02-05 01:57:15 +09:00]] 版))
<http://www.w3.org/TR/2013/NOTE-rif-xml-data-20130205/>

[33] [CITE@en-us[The oxy_xpath() Function]]
( ([TIME[2013-08-04 01:30:45 +09:00]] 版))
<http://www.oxygenxml.com/doc/ug-editor/concepts/dg-xpath-function.html>

[34] [CITE@en[XML Signature Syntax and Processing Version 2.0]]
( ([TIME[2013-04-23 19:47:19 +09:00]] 版))
<http://www.w3.org/TR/xmldsig-core2/#sec-Type-xml>

[35] [CITE@en[396966 – Xpath 2.0]]
( ([TIME[2013-10-31 23:53:10 +09:00]] 版))
<https://bugzilla.mozilla.org/show_bug.cgi?id=396966>

[37] ( ([TIME[2013-06-24 18:32:06 +09:00]] 版))
<http://www.iana.org/assignments/media-types/application/urc-uisocketdesc+xml>

[38] [CITE[eXtensible Access Control Markup Language (XACML) Version 3.0]]
( ([TIME[2013-01-23 02:00:00 +09:00]] 版))
<http://docs.oasis-open.org/xacml/3.0/xacml-3.0-core-spec-os-en.html#_Toc297001083>

[39] [CITE[eXtensible Access Control Markup Language (XACML) Version 3.0]]
( ([TIME[2013-01-23 02:00:00 +09:00]] 版))
<http://docs.oasis-open.org/xacml/3.0/xacml-3.0-core-spec-os-en.html#_Toc297001083>


[40] [CITE@en-US[DOM Event I/O Processor for SCXML]]
( ([TIME[2015-08-06 00:51:18 +09:00]] 版))
<http://www.w3.org/TR/2015/NOTE-dom-iop-20150806/>

[FIG(quote)[
[FIGCAPTION[
[41] ([TIME[2013-06-24 18:32:06 +09:00]] 版)
<https://www.iana.org/assignments/media-types/application/urc-uisocketdesc+xml>
]FIGCAPTION]

> XPath 2.0 fragments

]FIG]


[42] [CITE@EN[XQuery and XPath Full Text 3.0]]
( ([TIME[2015-11-20 06:32:18 +09:00]] 版))
<http://www.w3.org/TR/2015/REC-xpath-full-text-30-20151124/>

** XPath 3.0

[43] [CITE@EN[XML Path Language (XPath) 3.0]]
( ([TIME[2010-12-17 05:08:52 +09:00]] 版))
<http://www.w3.org/TR/2010/WD-xpath-30-20101214/>

[44] [CITE@EN[XPath and XQuery Functions and Operators 3.0]]
( ([TIME[2013-10-22 22:33:31 +09:00]] 版))
<http://www.w3.org/TR/2013/PR-xpath-functions-30-20131022/>

[45] [CITE@EN[XML Path Language (XPath) 3.0]]
( ([TIME[2013-10-22 23:01:14 +09:00]] 版))
<http://www.w3.org/TR/2013/PR-xpath-30-20131022/>

[46] [CITE@EN[XML Path Language (XPath) 3.0]]
( ([TIME[2014-04-08 07:58:50 +09:00]] 版))
<http://www.w3.org/TR/2014/REC-xpath-30-20140408/>

[47] [CITE@EN[XPath and XQuery Functions and Operators 3.0]]
( ([TIME[2014-04-08 07:02:07 +09:00]] 版))
<http://www.w3.org/TR/2014/REC-xpath-functions-30-20140408/>

[48] [CITE@EN[XPath and XQuery Functions and Operators 3.0]]
( ([TIME[2014-04-08 07:02:07 +09:00]] 版))
<http://www.w3.org/TR/xpath-functions-3/>

[49] [CITE@en[XSLT and XQuery Serialization 3.0]]
( ([TIME[2014-04-07 23:19:15 +09:00]] 版))
<http://www.w3.org/TR/xslt-xquery-serialization-3/>

[50] [CITE@EN[XQuery and XPath Full Text 3.0]]
( ([TIME[2015-03-11 08:45:07 +09:00]] 版))
<http://www.w3.org/TR/2015/CR-xpath-full-text-30-20150312/>

[51] [CITE@EN[XQuery and XPath Full Text 3.0 Requirements and Use Cases]]
( ([TIME[2015-03-12 09:09:57 +09:00]] 版))
<http://www.w3.org/TR/2015/WD-xpath-full-text-30-requirements-use-cases-20150312/>

[52] [CITE@EN[XQuery and XPath Full Text 3.0 Requirements and Use Cases]]
( ([TIME[2015-12-10 17:30:17 +09:00]] 版))
<http://www.w3.org/TR/2015/NOTE-xpath-full-text-30-requirements-use-cases-20151210/>

** XPath 3.1

[53] [CITE@EN[XML Path Language (XPath) 3.1]]
( ([TIME[2014-04-25 04:18:38 +09:00]] 版))
<http://www.w3.org/TR/2014/WD-xpath-31-20140424/>

[54] [CITE@EN[XPath and XQuery Functions and Operators 3.1]]
( ([TIME[2014-04-24 10:50:44 +09:00]] 版))
<http://www.w3.org/TR/2014/WD-xpath-functions-31-20140424/>

[55] [CITE@en[XQuery and XPath Data Model 3.1]]
( ([TIME[2014-04-24 10:43:48 +09:00]] 版))
<http://www.w3.org/TR/2014/WD-xpath-datamodel-31-20140424/>

[56] [CITE@en[XSLT and XQuery Serialization 3.1]]
( ([TIME[2014-04-24 10:54:46 +09:00]] 版))
<http://www.w3.org/TR/2014/WD-xslt-xquery-serialization-31-20140424/>

[57] [CITE@en[XQuery 3.1 Requirements and Use Cases]]
( ([TIME[2014-04-25 04:22:52 +09:00]] 版))
<http://www.w3.org/TR/2014/WD-xquery-31-requirements-20140424/>

[58] [CITE@EN[XQuery 3.1: An XML Query Language]]
( ([TIME[2014-04-25 04:20:55 +09:00]] 版))
<http://www.w3.org/TR/2014/WD-xquery-31-20140424/>

[59] [CITE@EN[XQueryX 3.1]]
( ([TIME[2014-04-24 10:55:33 +09:00]] 版))
<http://www.w3.org/TR/2014/WD-xqueryx-31-20140424/>

[60] [CITE@EN[XML Path Language (XPath) 3.1]]
( ([TIME[2014-12-18 06:56:21 +09:00]] 版))
<http://www.w3.org/TR/2014/CR-xpath-31-20141218/>

[61] [CITE@EN[XQuery 3.1: An XML Query Language]]
( ([TIME[2014-12-18 07:01:39 +09:00]] 版))
<http://www.w3.org/TR/2014/CR-xquery-31-20141218/>

[62] [CITE@EN[XQueryX 3.1]]
( ([TIME[2014-12-18 07:05:42 +09:00]] 版))
<http://www.w3.org/TR/2014/CR-xqueryx-31-20141218/>

[63] [CITE@EN[XPath and XQuery Functions and Operators 3.1]]
( ([TIME[2014-12-18 06:45:18 +09:00]] 版))
<http://www.w3.org/TR/2014/CR-xpath-functions-31-20141218/>

[64] [CITE@en[XQuery and XPath Data Model 3.1]]
( ([TIME[2014-12-18 07:34:29 +09:00]] 版))
<http://www.w3.org/TR/2014/CR-xpath-datamodel-31-20141218/>

[65] [CITE@en[XSLT and XQuery Serialization 3.1]]
( ([TIME[2015-02-19 08:41:10 +09:00]] 版))
<http://www.w3.org/TR/2015/CR-xslt-xquery-serialization-31-20150219/>

[66] [CITE@EN[XQuery 3.1: An XML Query Language]]
( ([TIME[2015-12-16 09:52:45 +09:00]] 版))
<http://www.w3.org/TR/2015/CR-xquery-31-20151217/>

[67] [CITE@EN[XML Path Language (XPath) 3.1]]
( ([TIME[2015-12-16 10:01:30 +09:00]] 版))
<http://www.w3.org/TR/2015/CR-xpath-31-20151217/>

[68] [CITE@en[XSLT and XQuery Serialization 3.1]]
( ([TIME[2015-12-16 10:03:33 +09:00]] 版))
<http://www.w3.org/TR/2015/CR-xslt-xquery-serialization-31-20151217/>

[69] [CITE@EN[XPath and XQuery Functions and Operators 3.1]]
([TIME[2016-12-13 16:27:14 +09:00]])
<https://www.w3.org/TR/2016/CR-xpath-functions-31-20161213/>

[70] [CITE@EN[XML Path Language (XPath) 3.1]]
([TIME[2017-01-15 12:14:28 +09:00]])
<https://www.w3.org/TR/2017/PR-xpath-31-20170117/>

[71] [CITE@en-US[XPath Next Community Group]]
([TIME[2017-03-16 20:25:25 +09:00]])
<https://www.w3.org/community/xpath-next/>

[72] [CITE@en[XPath-Next/README.md at master · XPath-Next/XPath-Next]]
([TIME[2017-03-16 20:25:35 +09:00]])
<https://github.com/XPath-Next/XPath-Next/blob/master/README.md>

[73] [CITE@en[XPath-Next/XPath-Next: Main site of information of XPath Next]]
([TIME[2017-03-16 20:29:54 +09:00]])
<https://github.com/XPath-Next/XPath-Next>

[74] [CITE[XPath-Next by XPath-Next]]
([TIME[2017-03-12 01:13:24 +09:00]])
<https://xpath-next.github.io/XPath-Next/>

[75] [[Schematron]]

[76] [CITE@EN[XML Path Language (XPath) 3.1]]
([TIME[2017-03-20 09:18:04 +09:00]])
<https://www.w3.org/TR/2017/REC-xpath-31-20170321/>

[77] [[XPath 3.1]] と [[XQuery 3.1]] とほとんど同じで少し違うんだけど、
なんでほとんど同じ内容をコピペした[[仕様書]]になってるんだろう。
[[XPath 2.0]] & [[XQuery 1.0]] 時代からもう何年も無駄なコピペ編集作業を続けるのは大変だと思うんだけど、
中の人は苦じゃないんだろうな。それとも [[XPath 2.0]] 派と [[XQuery]]
派のメンツみたいな何かがあるんだろうか。

[[XDM]] とか関数とかは共通の別仕様になってるんだから (それはそれで個々の仕様書の重複がなぜか多い気がするんだけど)、
[[XPath 2.0]] と [[XQuery]] の本体仕様書の共通部分ももっと統一して良いと思うんだけど。

[78] 統一しちゃうとどっちもほとんど同じじゃん、という本質的な問題が見えてしまうから、
敢えてわかりにくくしてるという説もあるか?