sdpl 2002notes 5: xslt1 5. document transformations n xslt (w3c rec. november 1999) –a language...

SDPL 2002 Notes 5: XSLT 1

5. Document Transformations5. Document Transformations

XSLT (W3C Rec. November 1999)XSLT (W3C Rec. November 1999)– A language for transforming XML documentsA language for transforming XML documents

» representative of tree-based transformation languages representative of tree-based transformation languages (DSSSL, MetaMorphosis, TranSID, …) (DSSSL, MetaMorphosis, TranSID, …)

– designed to be used designed to be used » primarily as part of XSL formattingprimarily as part of XSL formatting» also as an independent transformation languagealso as an independent transformation language

Our goal: to understand the basic model and Our goal: to understand the basic model and central features of the languagecentral features of the language– Overview and an exampleOverview and an example– Data model and processing modelData model and processing model


XSLT: OverviewXSLT: Overview

XSLT uses XML syntax for expressing XSLT uses XML syntax for expressing transformationstransformations– of a document of a document source treesource tree into a into a result treeresult tree

» result and source are separate treesresult and source are separate trees

– by by template rulestemplate rules Each (ordinary) template rules hasEach (ordinary) template rules has

– aa pattern pattern (matched against nodes of the source tree) (matched against nodes of the source tree)– a a template template as a bodyas a body

» instantiated to create fragments of the result treeinstantiated to create fragments of the result tree


Trans form ation P rocess

O utput P ro cess

X M L

T ext

H T M L

S tyleS heet

SourceDocument

Sourc e TreeR esult T ree

Overview of XSLT TransformationOverview of XSLT Transformation

Style Sheets and Template RulesStyle Sheets and Template Rules

AnAn xsl:stylesheetxsl:stylesheet (or(or xsl:transformxsl:transform) ) consists of template rules:consists of template rules:<xsl:template match="<xsl:template match="PatternPattern">">

TemplateTemplate  --></xsl:template></xsl:template>

Rule applied to nodes of source tree matched by Rule applied to nodes of source tree matched by the the PatternPattern – expressed using XML Path Language (XPath)expressed using XML Path Language (XPath)

TemplateTemplate consists of consists of» literal result tree fragments (elements, text), and literal result tree fragments (elements, text), and » XSLT instructions for creating further result tree fragments XSLT instructions for creating further result tree fragments


XPath in ShortXPath in Short

W3C Recommendation (November 1999)W3C Recommendation (November 1999)– a compact non-XML syntax for a compact non-XML syntax for addressing addressing

parts of XML documentsparts of XML documents– used also in other W3C languagesused also in other W3C languages

» XLink and XPointer (XLink and XPointer (drafts for hyperlinks in XML)drafts for hyperlinks in XML)» XQuery (draft, 12/2001, for querying XML)XQuery (draft, 12/2001, for querying XML)

– provides also typical primitives for manipulating provides also typical primitives for manipulating strings, numbersstrings, numbers and and truth valuestruth values

An XSL transformation exampleAn XSL transformation example

Transform below document to HTML:Transform below document to HTML:<?xml version='1.0'?><?xml version='1.0'?>

<?xml-stylesheet type="text/xsl" href="walsh.xsl" ?><?xml-stylesheet type="text/xsl" href="walsh.xsl" ?>

 

<doc><title>My Document</title><doc><title>My Document</title>

<para>This is a <em>short</em> document.</para><para>This is a <em>short</em> document.</para>

<para>It only exists to <em>demonstrate a <para>It only exists to <em>demonstrate a

<em>simple</em> XML document</em>.</para><em>simple</em> XML document</em>.</para>

<figure><title>My Figure</title> <figure><title>My Figure</title>

<graphic fileref="myfig.jpg"/></figure><graphic fileref="myfig.jpg"/></figure>

</doc></doc>

Example style sheet beginsExample style sheet begins

<xsl:stylesheet version=<xsl:stylesheet version="1.0""1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:template match="<xsl:template match="//"> ">  <HTML><HEAD><TITLE>A Document</TITLE></HEAD> <HTML><HEAD><TITLE>A Document</TITLE></HEAD> <BODY><BODY> 

<xsl:apply-templates /> <xsl:apply-templates /> </BODY></BODY> </HTML></HTML> </xsl:template></xsl:template>

<xsl:template match="<xsl:template match="doc/titledoc/title"> "> <H1><H1><xsl:apply-templates /><xsl:apply-templates /></H1></H1>

</xsl:template></xsl:template>


Example (Example (paraparass and and emphemphs)s)

<xsl:template match="<xsl:template match="parapara"> "> <P><P><xsl:apply-templates /><xsl:apply-templates /></P></P>

</xsl:template> </xsl:template>

<xsl:template match="<xsl:template match="emem"> "> <I><I><xsl:apply-templates /><xsl:apply-templates /></I></I>


<xsl:template match="<xsl:template match="em/emem/em"> "> <B><B><xsl:apply-templates /><xsl:apply-templates /></B></B>


Example (Example (figurefigures)s)

<xsl:template match="<xsl:template match="figurefigure"> ">  by counting all figures in the document: --><DIV><B>Figure <DIV><B>Figure <xsl:number level="any" <xsl:number level="any"

count="figure"/>count="figure"/>. </B> . </B> <BR /> <BR /> <xsl:apply-templates select="<xsl:apply-templates select="graphicgraphic" /> " />

<xsl:apply-templates select="<xsl:apply-templates select="titletitle" /> " />

</DIV></DIV>

Example (end of style sheet)Example (end of style sheet)

<xsl:template match="<xsl:template match="graphicgraphic"> "> <IMG><IMG>   <xsl:attribute name=" <xsl:attribute name="srcsrc"> ">  element's fileref attribute to it: -->

<xsl:value-of select=" <xsl:value-of select="@fileref@fileref" /> " /> </xsl:attribute> </xsl:attribute>

</IMG> </IMG> </xsl:template></xsl:template> <xsl:template match="<xsl:template match="figure/titlefigure/title"> ">

<B> <B> <xsl:apply-templates /><xsl:apply-templates /> </B> </B> </xsl:template> </xsl:template> 

</xsl:stylesheet></xsl:stylesheet>


Result (edited for readability)Result (edited for readability)

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">Transitional//EN">

<HTML><HEAD><TITLE>A Document</TITLE></HEAD><HTML><HEAD><TITLE>A Document</TITLE></HEAD>

<BODY> <H1><BODY> <H1>My DocumentMy Document</H1></H1>

<P><P>This is a This is a <I><I>shortshort</I></I> document. document.</P></P>

<P><P>It only exists to It only exists to <I><I>demonstrate a demonstrate a <B><B>simplesimple</B></B> XML XML documentdocument</I></I>..</P></P>

<DIV><DIV>

<B>Figure <B>Figure 11. </B> <BR>. </B> <BR>

<IMG src<IMG src="myfig.jpg"="myfig.jpg"><B>><B>My FigureMy Figure</B></B>

</DIV></DIV>

</BODY></BODY>

</HTML></HTML>


What use of XSL or XSLT?What use of XSL or XSLT?

XSL can be used in different waysXSL can be used in different ways– for offline document formattingfor offline document formatting

» produce, say, PDF from XML by an XSL style sheet produce, say, PDF from XML by an XSL style sheet (using XSLT + XSL formatting objects)(using XSLT + XSL formatting objects)

– for offline document manipulationfor offline document manipulation» transform XML into other form (XML/HTML/text) transform XML into other form (XML/HTML/text)

using XSLTusing XSLT

– for online document deliveryfor online document delivery» in a Web serverin a Web server» in a Web browser (if the browser supports)in a Web browser (if the browser supports)


XSLT in online document deliveryXSLT in online document delivery

XSLT in a browserXSLT in a browser– defines rendering of XML documentsdefines rendering of XML documents– approach of Microsoft Internet Explorer 5approach of Microsoft Internet Explorer 5

» transformation of XML to HTML on the fly in browsertransformation of XML to HTML on the fly in browser» NBNB: Microsoft's XSLT implementation differs from XSLT 1.0: Microsoft's XSLT implementation differs from XSLT 1.0

(a new one exists but has to be installed separately)(a new one exists but has to be installed separately)

XSLT in a Web serverXSLT in a Web server– an HTTP request for an XML document served by an HTTP request for an XML document served by

transforming XML on the fly to HTML (or other format) transforming XML on the fly to HTML (or other format) in the serverin the server


Data Model of XSLT and XPathData Model of XSLT and XPath

Documents viewed as abstract, logical tree Documents viewed as abstract, logical tree structuresstructures

Seven types of tree nodesSeven types of tree nodes– rootroot (additional parent of document element) (additional parent of document element)– elementelement nodes nodes– attributeattribute nodes nodes– texttext nodes nodes– nodes for nodes for commentscomments, , processing instructionsprocessing instructions and and

namespacesnamespaces NBNB: Entities are expanded : Entities are expanded no entity nodes no entity nodes


XSLT/XPath document treesXSLT/XPath document trees

Element nodes have elements, text nodes, Element nodes have elements, text nodes, comments and processing instructions of their comments and processing instructions of their (direct) (direct) contentcontent as child nodes as child nodes– NB: attribute nodes not considered childrenNB: attribute nodes not considered children– the the valuevalue of an element node is the concatenation of its of an element node is the concatenation of its

text-node descendantstext-node descendants Nodes have a complete Nodes have a complete document orderdocument order

– root node first, otherwise according to the order of the root node first, otherwise according to the order of the first character of the XML markup for each nodefirst character of the XML markup for each node

– > element node precedes it's attribute nodes, which > element node precedes it's attribute nodes, which precede any content nodes of the elementprecede any content nodes of the element


XSLT/XPath trees: ExampleXSLT/XPath trees: Example

Similar to the DOM structure model, with slight Similar to the DOM structure model, with slight differencesdifferences– value of an element: its full textual content value of an element: its full textual content

(In DOM: (In DOM: nullnull))– no names for text nodes, comment nodes, etc.no names for text nodes, comment nodes, etc.

(In DOM: (In DOM: "#text""#text", , "#comment""#comment", etc. , etc.

Example document:Example document:<article>Written by <fig file="pekka.jpg" <article>Written by <fig file="pekka.jpg"

caption="The caption="The Lecturer"/> Lecturer"/> the lecturer.</article>the lecturer.</article>


XSLT/XPath trees: ExampleXSLT/XPath trees: Example

"W ritte n b y the le c ture r."

"W ritte n b y the le c ture r."

root

""

elem ent

"artic le "

text

""

"W ritte n b y "

elem ent

"f ig "

""

text

""

" the le c ture r."

attribute attribute

"cap tio n" "f ile "

"The Lec turer" "p e kka.jp g "

Legend: type

value

nam e

<article>Written by <article>Written by <fig <fig file="pekka.jpg" file="pekka.jpg" caption="The caption="The Lecturer"/> the Lecturer"/> the lecturer.</article>lecturer.</article>


XPath ExpressionsXPath Expressions

Used for selecting source tree nodes, conditional Used for selecting source tree nodes, conditional processing, and generating new text contentprocessing, and generating new text content– return return node-sets, truth values, numbers node-sets, truth values, numbers oror strings strings– can select any parts of source tree (can select any parts of source tree (node-setnode-set) for ) for

processing, using … processing, using … Location pathsLocation paths

– the most characteristic of XPath expressionsthe most characteristic of XPath expressions– evaluated with respect to a evaluated with respect to a context nodecontext node

» often the often the current nodecurrent node matched by the template pattern matched by the template pattern

– resultresult: set of nodes selected by the location path: set of nodes selected by the location path


Location paths (1)Location paths (1)

Consist of Consist of location stepslocation steps separated by ' separated by '//''– each step produces a set of nodeseach step produces a set of nodes– steps evaluated left-to-right, steps evaluated left-to-right,

each node in turn acting as a context nodeeach node in turn acting as a context node Complete form of a location step: Complete form of a location step:

AxisNameAxisName:::: NodeTestNodeTest ( ([[PredicateExprPredicateExpr]])*)*

– axisaxis specifies the tree relationship between the context specifies the tree relationship between the context node and the selected nodes node and the selected nodes

– node testnode test restricts the type and and name of nodes restricts the type and and name of nodes– further filtered by 0 or more further filtered by 0 or more predicatespredicates



In total 13 axesIn total 13 axes– child, descendant, parent, ancestor, following-child, descendant, parent, ancestor, following-sibling, preceding-sibling, following, preceding, sibling, preceding-sibling, following, preceding, attribute, self, descendant-or-self, ancestor-or-attribute, self, descendant-or-self, ancestor-or-self, namespaceself, namespace

Node tests (slightly simplified)Node tests (slightly simplified)– NameName: any : any elementelement node with name node with name NameName

(on an attribute axis, any attribute node with name (on an attribute axis, any attribute node with name NameName))– **: any element node (on an attribute axis, any attribute node): any element node (on an attribute axis, any attribute node)– text()text(): any text node: any text node– node()node(): any node of any type: any node of any type



Abbreviations in location stepsAbbreviations in location steps– 'child::''child::' can be omitted can be omitted– 'attribute::''attribute::' can be shortened to can be shortened to ''@@''– ''/descendant-or-self::node()/'/descendant-or-self::node()/' shortened to shortened to ''////''

("go down any number of levels")("go down any number of levels")– 'self::node()''self::node()' can be shortened to can be shortened to ''..'' (period)(period)– 'parent::node()''parent::node()' can be shortened to can be shortened to ''....''

– Predicate 'Predicate '[position()=[position()=nn]]' for testing occurrence position ' for testing occurrence position nn can can be shortened to'be shortened to' [ [nn]]''

''//' ' in the beginning sets context to the root nodein the beginning sets context to the root node Syntax resembles Linux/Unix file path namesSyntax resembles Linux/Unix file path names


XPath Axes and Their OrientationXPath Axes and Their Orientation

Axes are oriented away from the context nodeAxes are oriented away from the context node(except (except attribute attribute and and namespace namespace axes, which are axes, which are unordered sets)unordered sets)– the the position() position() for the closest node for the closest node = 1 = 1– for the most remote node, for the most remote node, position() = last()position() = last()

1

C o nte xtno de :

The simplest axis,The simplest axis, self: self:



parent:parent:

1 C ontextnode :



ancestor:ancestor: 2

1

ancestor-or-self:ancestor-or-self:3

2

1



child:child:

431 2

C ontextnode :



descendant:descendant:

871 4

2 3 65 9

descendant-or-self:descendant-or-self: 1

982 5

3 4 76 1 0



preceding-sibling:preceding-sibling:

2 1

following-sibling:following-sibling:

21



following :following :

21

3

preceding:preceding:

3

2 1


Semantics of Location Paths (example)Semantics of Location Paths (example)

{2, 5, 7}{2, 5, 7}

AA

BB

context nodecontext node

CC"txt""txt"AA BB

BBCC55

884433

22

11

66

77

*/node()/parent::B[child::A]*/node()/parent::B[child::A]

{3, 4, 6, 8}{3, 4, 6, 8} {2, 5, 7}{2, 5, 7}

final value: {2}final value: {2}


Location path examples (1)Location path examples (1)

chapchap children of current node:children of current node: ./chap./chap (or equivalently:(or equivalently: chapchap, or, or ./child::node()[name()='chap']./child::node()[name()='chap']))

The document element The document element (child element of root node):(child element of root node): /*/*

Elements Elements chapter chapter anywhere (below the root): anywhere (below the root): //chapter//chapter

All All chapterchapters with attributes with attribute type="intro"type="intro": : //chapter[@type='intro']//chapter[@type='intro']

the previousthe previous chapter chapter siblingsibling: : preceding-sibling::chapter[1]preceding-sibling::chapter[1]



All child elements having an attributeAll child elements having an attribute typetype: : *[@type]*[@type]

NBNB: use of node sets as truth values: : use of node sets as truth values: empty - empty - falsefalse; non-empty - ; non-empty - truetrue

All child elements of anyAll child elements of any author author child:child: author/*author/*

sectsections whoseions whose type type attribute equalsattribute equals style style attribute of the document element:attribute of the document element:

//sect[@type = /*/@style]//sect[@type = /*/@style] First First authorauthor child, and previous to the last: child, and previous to the last:

author[1], author[last()-1]author[1], author[last()-1]



Predicate expressions can be Boolean Predicate expressions can be Boolean combinations:combinations:– child elements child elements authorauthor with a with a publpubl child, but without child, but without degreedegree or or awardaward children:children:

author[publ and not(degree or award)]author[publ and not(degree or award)] Closest Closest chapchap ancestor (and highest):ancestor (and highest):

ancestor::chap[1] ancestor::chap[1] (ancestor::chap[last()]) (ancestor::chap[last()])

authorauthor of the highestof the highest sectsect ancestor that is ancestor that is contained in ancontained in an appappendix:endix: ancestor::sect[ancestor::app][last()]/authorancestor::sect[ancestor::app][last()]/author


XSLT PatternsXSLT Patterns

Main use in match attributes of template rules:Main use in match attributes of template rules:<xsl:template match="<xsl:template match="PatternPattern">">

Restricted location path expressions:Restricted location path expressions:– may use onlymay use only childchild and and attributeattribute axes and operatorsaxes and operators

''////' ' and and ''//''» can use arbitrary predicate expressions can use arbitrary predicate expressions [[ExprExpr]]

– may begin withmay begin with id(id(''IdValIdVal''))(for selecting element nodes by ID attribute values)(for selecting element nodes by ID attribute values)

– alternative patterns separated by 'alternative patterns separated by '||' ' (node-set union (node-set union operator)operator)


XSLT Patterns: SemanticsXSLT Patterns: Semantics

A location path pattern A location path pattern PP is of form is of form StepStep11§ § StepStep2 2 § …§ § …§ StepStepnn-1-1§ § StepStepn n ,,

where each separator § is either 'where each separator § is either '//' or '' or '////' ' Pattern Pattern PP matches a node matches a node nn iff the rightmost step iff the rightmost step StepStepn n

matches matches n,n, and a suitable node and a suitable node v v matches the prefix matches the prefix StepStep11§ §

StepStep2 2 § …§ § …§ StepStepnn-1 -1 of of PP : :

– if the rightmost § is 'if the rightmost § is '//'', , vv must be the parent of must be the parent of nn– if the rightmost § is 'if the rightmost § is '////', ', vv may be any ancestor of may be any ancestor of nn

That is, there's a path That is, there's a path ((StepStepnn,..., ,..., StepStep11) from ) from nn towards root towards root


XSLT Patterns: ExamplesXSLT Patterns: Examples

PatternPattern sect-head | section/head sect-head | section/head

matches any element with namematches any element with name sect-headsect-head, and any, and any headhead elements directly below aelements directly below a sectionsection

For a match with patternFor a match with pattern /appendix//ulist/item[1] /appendix//ulist/item[1]

a node has to be the first a node has to be the first itemitem element in aelement in a ulistulist element which is contained in anelement which is contained in an appendixappendix, which is the , which is the document elementdocument element


XSLT Processing ModelXSLT Processing Model

0. Parse the document into a 0. Parse the document into a source treesource tree

1. Construct the 1. Construct the result treeresult tree by applying by applying template rulestemplate rules to the source tree to the source tree» may contain text, formatting objects and arbitrary may contain text, formatting objects and arbitrary

elementselements

2. Serialize the result tree (as XML, HTML or 2. Serialize the result tree (as XML, HTML or text), or interpret it to produce formatted output text), or interpret it to produce formatted output (in case of full XSL processing)(in case of full XSL processing)


XSL Tree ConstructionXSL Tree Construction

Start at the source tree root; Start at the source tree root;

whilewhile (unprocessed source nodes left) (unprocessed source nodes left) dodo

Find matching template rules; Find matching template rules; Choose one rule (the one with highest Choose one rule (the one with highest prioritypriority););

Instantiate rule template in the context of the current Instantiate rule template in the context of the current node; Add the result to the result tree;node; Add the result to the result tree;

Recursively process any source nodes selected by XSLT Recursively process any source nodes selected by XSLT instructions (instructions (apply-templates, for-eachapply-templates, for-each) in the ) in the template;template;

endwhileendwhile;;


Selecting among multiple matching rulesSelecting among multiple matching rules

Priority of a rule can be specified explicitly: Priority of a rule can be specified explicitly: <xsl:template priority="2.0"><xsl:template priority="2.0"> … …

Default priorities based on the Default priorities based on the matchmatch pattern: pattern:– 0 for simple name tests 0 for simple name tests (like (like para, @hrefpara, @href))– negative for less specific patterns negative for less specific patterns

e.g., e.g., *, @*, node()*, @*, node()– 0.5 for more complex patterns0.5 for more complex patterns

Multiple matching rules with the same maximum Multiple matching rules with the same maximum priority is an error - Processor may recover by priority is an error - Processor may recover by (quietly!) choosing the (quietly!) choosing the last onelast one of those rules of those rules


Application of template rulesApplication of template rules

Without a Without a selectselect attribute attribute <xsl:apply-templates /><xsl:apply-templates />

processes all children of current nodeprocesses all children of current node– > > Default behaviour: top-down traversal of source treeDefault behaviour: top-down traversal of source tree

Otherwise theOtherwise the selectselected nodes are processed ed nodes are processed – in in document order document order (if not sorted with (if not sorted with xsl:sortxsl:sort))

Built-in rulesBuilt-in rules allow recursive traversal to proceed allow recursive traversal to proceed gracefully in the absence of matching rules gracefully in the absence of matching rules

Default rules for elements and contentDefault rules for elements and content

Built-in rule for the root and element nodes:Built-in rule for the root and element nodes: <xsl:template match="/ | *"><xsl:template match="/ | *">

<xsl:apply-templates /><xsl:apply-templates /> </xsl:template</xsl:template>>

Built-in rule for text and attribute nodes:Built-in rule for text and attribute nodes: <xsl:template match="text() | @*"><xsl:template match="text() | @*">of current node: --> <xsl:<xsl:value-ofvalue-of select="." /> select="." />

</xsl:template</xsl:template>> Low priorityLow priority can be overriddencan be overridden

A (Tricky) Processing Example A (Tricky) Processing Example

Consider transforming documentConsider transforming document<A><A><C>c1</C><B>bb<C>c2</C></B><D>dd</D><C>c3</C><C>c1</C><B>bb<C>c2</C></B><D>dd</D><C>c3</C></A></A>

with the below rules:with the below rules:<xsl:template match="/"> <xsl:template match="/"> 

<R><xsl:<R><xsl:apply-templatesapply-templates select="//B" /></R> select="//B" /></R></xsl:template></xsl:template>

<xsl:template match="B"> <xsl:template match="B"> <NewB><NewB>New:New: <xsl: <xsl:apply-templatesapply-templates select="../C" /> <xsl:select="../C" /> <xsl:apply-templatesapply-templates /> /> </NewB></NewB>


Processing example (2)Processing example (2)

The resultThe result<R><NewB><R><NewB>New:New: c1c3bbc2</NewB></R> c1c3bbc2</NewB></R>

is obtained as follows: is obtained as follows: 1. 1. Rule 1 matches the root node Rule 1 matches the root node Element node Element node RR is added is added

to the result; Instruction to the result; Instruction <xsl:apply-templates <xsl:apply-templates

select="//B" />select="//B" /> selects the (only)selects the (only) BB element for element for processing (which will produce the contents of node processing (which will produce the contents of node RR). ).

2. 2. Rule 2 with patternRule 2 with pattern "B" "B" creates into result tree acreates into result tree a NewB NewB element node with text node element node with text node ""New:New: " " as its first child.as its first child.


Processing example (3)Processing example (3)

3. Instruction 3. Instruction <xsl:apply-templates select="../C"/><xsl:apply-templates select="../C"/> selects element selects element CC siblings of current node (siblings of current node (BB). The built-in ). The built-in element rule applies to these, and the built-in text rule to element rule applies to these, and the built-in text rule to their children. their children. Result: text nodesResult: text nodes " "c1c1" " and and ""c3c3" " become the next become the next children ofchildren of NewBNewB..

4. Instruction 4. Instruction <xsl:apply-templates /><xsl:apply-templates /> in the context of in the context of element node element node BB selects its children, selects its children, ""bb"bb" and and <C>c2</C><C>c2</C>, for processing. The built-in text rule inserts , for processing. The built-in text rule inserts value value ""bb"bb" to the result tree, and the to the result tree, and the C C element node element node becomesbecomes "c2""c2" in the result (similarly to step 3). in the result (similarly to step 3).


Is it Really So Tricky?Is it Really So Tricky?

In practice: SeldomIn practice: Seldom– A computer scientist wants to understand how a model A computer scientist wants to understand how a model

really works … really works …

XSLT is high-level declarative language for XSLT is high-level declarative language for describing transformationsdescribing transformations– Normally no need to think about execution in so much Normally no need to think about execution in so much

detail; Often sufficient just to specify declarative rules detail; Often sufficient just to specify declarative rules to handle different cases, liketo handle different cases, like

<xsl:template match="<xsl:template match="parapara"> "> <P><P><xsl:apply-templates /><xsl:apply-templates /></P></P>


sdpl 2002notes 5: xslt1 5. document transformations n xslt (w3c rec. november 1999) –a language...

Documents

document slide

short document

simple xml document

document source tree

figure slide

result tree slide

template rules n

template template n