BaH.Libxslt:

Libxslt

Libxslt is the XSLT processor developed for the Gnome project.
This is the BlitzMax implementation of the libxslt library.

XSLT itself is a an XML language to define transformation for XML. Libxslt is based on libxml2 the XML library developed for the Gnome project.
For more information on XSLT, visit the XSLT website.

You need the BaH.Libxml module in order to build applications which use Libxslt.

Here are some key points about libxslt:

Libxslt is based on libxml for XML parsing, tree manipulation and XPath support
This library is released under the MIT Licence
Though not designed primarily with performances in mind, libxslt seems to be a relatively fast processor.

Basic Use

Doing an XSLT transformation can be done in a few simple steps:

configure the parser for XSLT:

xmlSubstituteEntitiesDefault();
xmlLoadExtDtdDefaultValue = 1
parse the stylesheet with TxsltStylesheet.parseStylesheetFile()
parse the document with TxmlDoc.parseFile()
apply the stylesheet using applyStylesheet()
save the result using saveResultToFilename() if needed set xmlIndentTreeOutput to 1

Tutorial

See the Libxslt Tutorial for an introduction to using the libxslt module.

Constants

Const XSLT_DEFAULT_URL:String
Description	The XSLT "vendor" URL for this processor.

Const XSLT_DEFAULT_VENDOR:String
Description	The XSLT "vendor" string for this processor.

Const XSLT_NAMESPACE:String
Description	The XSLT specification namespace.

Const XSLT_PARSE_OPTIONS:Int
Description	The set of options to pass to an xmlReadxxx when loading files for XSLT consumption.

Functions

Function xsltCleanupGlobals()
Description	Unregister all global variables set up by the XSLT library.

Types

Type TxsltCompMatch
Description	An XSLT CompMatch.

Method free()
Description	Free up the memory allocated by all the elements of the CompMatch.

Method testCompMatchList:Int(context:TxsltTransformContext, node:TxmlNode)
Returns	1 if it matches, 0 if it doesn't and -1 in case of failure.
Description	Test whether the node matches one of the patterns in the list.
Information	Parameters: context : an XSLT process context node : a node

Function compilePattern:TxsltCompMatch(pattern:String, doc:TxmlDoc, node:TxmlNode, style:TxsltStylesheet, runtime:TxsltTransformContext)
Returns	The generated pattern list or Null in case of failure.
Description	Compile the XSLT pattern and generates a list of precompiled form suitable for fast matching.
Information	Parameters: pattern : an XSLT pattern doc : the containing document node : the containing element style : the stylesheet runtime : the transformation context, if done at run-time

Type TxsltDocument
Description	An XSLT Document.

Method freeDocumentKeys()
Description	Free the keys associated to a document.

Function loadDocument:TxsltDocument(context:TxsltTransformContext , uri:String)
Returns	The new TxsltDocument or Null in case of error.
Description	Try to load a document (not a stylesheet) within the XSLT transformation context.
Information	Parameters: context : an XSLT transformation context uri : the computed URI of the document

Function loadStyleDocument:TxsltDocument(style:TxsltStylesheet , uri:String)
Returns	The new TxsltDocument or Null in case of error.
Description	Try to load a stylesheet document within the XSLT transformation context.
Information	Parameters: style : an XSLT style sheet uri : the computed URI of the document

Function newDocument:TxsltDocument(context:TxsltTransformContext, doc:TxmlDoc)
Returns	The new TxsltDocument.
Description	Register a new document, apply key computations.
Information	Parameters: context : an XSLT transformation context (or Null) doc : a parsed XML document

Function newStyleDocument:TxsltDocument(style:TxsltStylesheet, doc:TxmlDoc)
Returns	The new TxsltDocument.
Description	Register a new document, apply key computations.
Information	Parameters: style : an XSLT style sheet doc : a parsed XML document

Type TxsltElemPreComp
Description	An XSLT ElemPreComp.

Method getType:Int()

Description

Returns the type of this elemement.

Information

The following lists possible types:

Constant
XSLT_FUNC_COPY
XSLT_FUNC_SORT
XSLT_FUNC_TEXT
XSLT_FUNC_ELEMENT
XSLT_FUNC_ATTRIBUTE
XSLT_FUNC_COMMENT
XSLT_FUNC_PI
XSLT_FUNC_COPYOF
XSLT_FUNC_VALUEOF
XSLT_FUNC_NUMBER
XSLT_FUNC_APPLYIMPORTS
XSLT_FUNC_CALLTEMPLATE
XSLT_FUNC_APPLYTEMPLATES
XSLT_FUNC_CHOOSE
XSLT_FUNC_IF
XSLT_FUNC_FOREACH
XSLT_FUNC_DOCUMENT
XSLT_FUNC_WITHPARAM
XSLT_FUNC_PARAM
XSLT_FUNC_VARIABLE
XSLT_FUNC_WHEN
XSLT_FUNC_EXTENSION

Type TxsltTemplate
Description	An XSLT Template.

Type TxsltStylesheet
Description	An XSLT Stylesheet.

Method addKey:Int(name:String, nameURI:String, match:String, use:String, inst:TxmlNode)
Returns	0 in case of success, and -1 in case of failure.
Description	Add a key definition to the stylesheet.
Information	Parameters: name : the key name or Null nameURI : the name URI or Null match : the match value use : the use value inst : the key instruction

Method addTemplate:Int(cur:TxsltTemplate, mode:String, modeURI:String)
Returns	-1 in case of error, 0 otherwise.
Description	Register the XSLT pattern associated to cur.
Information	Parameters: cur : an XSLT template mode : the mode name or Null modeURI : the mode URI or Null

Method allocateExtra:Int()
Returns	The number of the slot.
Description	Allocate an extra runtime information slot statically while compiling the stylesheet and return its number.

Method applyStylesheet:TxmlDoc(doc:TxmlDoc)
Returns	The result document or Null in case of error.
Description	Apply the stylesheet to the document.
Information	NOTE: This may lead to a non-wellformed output, XML wise ! Parameters: doc : a parsed XML document

Method cleanupTemplates()
Description	Cleanup the state of the templates used by the stylesheet and the ones it imports.

Method compileAttr(attr:TxmlAttribute)

Description

Precompile an attribute in a stylesheet.

Information

Basically it checks if it is an attrubute value template, and if yes establish some structures needed to process it at transformation time.

Parameters:

attr : the attribute coming from the stylesheet

Method documentComp:TxsltElemPreComp(inst:TxmlNode)
Returns	A precompiled data structure for the element.
Description	Pre process an XSLT-1.1 document element.
Information	Parameters: inst : the instruction in the stylesheet

Method free()
Description	Free up the memory allocated to the sheet.

Method freeAttributeSetsHashes()
Description	Free up the memory used by attribute sets.

Method freeKeys()
Description	Free up the memory used by XSLT keys in the stylesheet.

Method freeNamespaceAliasHashes()
Description	Free up the memory used by namespaces aliases.

Method freeStyleDocuments()
Description	Free up all the space used by the loaded documents.

Method freeStylePreComps()
Description	Free up the memory allocated by all precomputed blocks.

Method freeTemplateHashes()
Description	Free up the memory used by addTemplate / getTemplate mechanism.

Method namespaceAlias(node:TxmlNode)
Description	Read the stylesheet-prefix and result-prefix attributes, register them as well as the corresponding namespace.
Information	Parameters: node : the xsl:namespace-alias node

Method nextImport:TxsltStylesheet()
Returns	The next stylesheet or Null if it was the last one.
Description	Find the next stylesheet in import precedence.

Method parseStylesheetAttributeSet(node:TxmlNode)
Description	Parse an XSLT stylesheet attribute-set element.
Information	Parameters: node : the "attribute-set" element

Method parseStylesheetImport:Int(node:TxmlNode)
Returns	0 in case of success -1 in case of failure.
Description	Parse an XSLT stylesheet import element.
Information	Parameters: node : the import element

Method parseStylesheetInclude:Int(node:TxmlNode)
Returns	0 in case of success -1 in case of failure.
Description	Parse an XSLT stylesheet include element.
Information	Parameters: node : the include node

Method parseStylesheetOutput(node:TxmlNode)
Description	Parse an XSLT stylesheet output element and record information related to the stylesheet output.
Information	Parameters: node : the "output" element

Method parseStylesheetProcess:TxsltStylesheet(doc:TxmlDoc)
Returns	the value of the 'ret' parameter if everything went right, Null if something went amiss.
Description	Parse the XSLT stylesheet adding the associated structures.
Information	Parameters: doc : an TxmlDoc parsed XML

Method parseTemplateContent(templ:TxmlNode)
Description	parse a template content-model Clean-up the template content from unwanted ignorable blank nodes and process xslt:text.
Information	Parameters: templ : the container node (can be a document for literal results)

Method resolveStylesheetAttributeSet()
Description	Resolve the references between attribute sets.

Method saveResultToFilename:Int(url:String, res:TxmlDoc, compression:Int = 0)
Returns	The number of byte written or -1 in case of failure.
Description	Save the result res obtained by applying the stylesheet to a URL / filename.
Information	Parameters: url : a filename or URL res : the result TxmlDoc compression : the compression factor (0 - 9 inclusive)

Method stylePreCompute(inst:TxmlNode)
Description	Precompute an XSLT stylesheet element.
Information	Parameters: inst : the instruction in the stylesheet

Function newStylesheet:TxsltStylesheet()
Returns	The new TxsltStylesheet or Null in case of error.
Description	Create a new XSLT Stylesheet.

Function parseStylesheetDoc:TxsltStylesheet(doc:TxmlDoc)
Returns	A new XSLT stylesheet structure.
Description	Parse an XSLT stylesheet building the associated structures.
Information	Parameters: doc : an TxmlDoc parsed XML

Function parseStylesheetFile:TxsltStylesheet(filename:String)
Returns	A new XSLT stylesheet structure.
Description	Load and parse an XSLT stylesheet.
Information	Parameters: filename : the filename/URL to the stylesheet

Type TxsltTransformContext
Description	An XSLT transformation context.

Method allocateExtraCtxt:Int()
Returns	the number of the slot.
Description	Allocate an extra runtime information slot at run-time and return its number.
Information	This makes sure there is a slot ready in the transformation context.

Method applyStripSpaces(node:TxmlNode)
Description	Strip the unwanted ignorable spaces from the input tree.
Information	Parameters: node : the root of the XML tree

Method attrListTemplateProcess:TxmlAttribute(target:TxmlNode, cur:TxmlAttribute)
Returns	A new TxmlAttribute object, or Null in case of error.
Description	Do a copy of an attribute list with attribute template processing.
Information	Parameters: target : the element where the attributes will be grafted cur : the first attribute

Method attrTemplateProcess:TxmlAttribute(target:TxmlNode, cur:TxmlAttribute)
Returns	The attribute replacement.
Description	Process the given attribute and return the new processed copy.
Information	Parameters: target : the result node cur : the attribute template node

Method attrTemplateValueProcess:String(value:String)
Returns	The computed string value or Null.
Description	Process the given node and return the new string value.
Information	Parameters: value : the attribute template node value

Method attrTemplateValueProcessNode:String(value:String, node:TxmlNode)
Returns	The computed string value or Null.
Description	Process the given string, allowing to pass a namespace mapping context and return the new string value.
Information	Parameters: value : the attribute template node value node : the node hosting the attribute

Method createRVT:TxmlDoc()
Returns	The result value tree or Null in case of error.
Description	Create a result value tree.

Method evalAttrValueTemplate:String(node:TxmlNode, name:String, namespace:String)
Returns	The computed string value or Null.
Description	Evaluate a attribute value template.
Information	i.e. the attribute value can contain expressions contained in curly braces ({}) and those are substituted by they computed value. Parameters: node : the stylesheet node name : the attribute QName namespace : the attribute namespace URI

Method evalAVT:String(avt:String, node:TxmlNode)
Returns	The computed string value or Null.
Description	Process the given AVT, and return the new string value.
Information	Parameters: avt : the precompiled attribute value template info node : the node hosting the attribute

Method evalStaticAttrValueTemplate:String(node:TxmlNode, name:String, namespace:String)
Returns	The static string value or Null.
Description	Check if an attribute value template has a static value.
Information	i.e. the attribute value does not contain expressions contained in curly braces ({}) Parameters: node : the stylesheet node name : the attribute Name namespace : the attribute namespace URI

Method evalTemplateString:String(node:TxmlNode, parent:TxmlNode)
Returns	The computed string value or Null.
Description	Evaluate a template string value.
Information	i.e. the parent list is interpreter as template content and the resulting tree string value is returned. This is needed for example by xsl:comment and xsl:processing-instruction. Parameters: node : the stylesheet node parent : the content parent

Method evalXPathString:String(comp:TxmlXPathCompExpr)
Returns	The computed string value or Null.
Description	Process the expression using XPath and get a string.
Information	Parameters: comp : the compiled XPath expression

Method findDocument:TxsltDocument(doc:TxmlDoc)
Returns	The desired xsltDocument or Null in case of error.
Description	Try to find a document within the XSLT transformation context.
Information	Parameters: doc : a parsed XML document

Method findElemSpaceHandling:Int(node:TxmlNode)
Returns	1 if space should be stripped, 0 if not, and 2 if everything should be CDTATA wrapped.
Description	Find strip-space or preserve-space informations for an element respect the import precedence or the wildcards.
Information	Parameters: node : an XML node

Method findTemplate:TxsltTemplate(name:String, nameURI:String)
Returns	The TxsltTemplate or Null if not found.
Description	Finds the named template, apply import precedence rule.
Information	Parameters: name : the template name nameURI : the template name URI

Method freeDocuments()
Description	Free up all the space used by the loaded documents.

Method freeRVTs()
Description	Free all the registered result value tree of the transformation.

Method getKey:TxmlNodeSet(name:String, nameURI:String, value:String)
Returns	The nodeset resulting from the query or Null.
Description	Lookup a key.
Information	Parameters: name : the key name or Null nameURI : the name URI or Null value : the key value to look for

Method getNamespace:TxmlNs(curNode:TxmlNode, namespace:TxmlNs, out:TxmlNode)
Returns	The namespace node to use or Null.
Description	Find the right namespace value for this prefix.
Information	If needed create and add a new namespace decalaration on the node Handle namespace aliases. Parameters: curNode : the input node namespace : the namespace out : the output node (or its parent)

Method getPlainNamespace:TxmlNs(curNode:TxmlNode, namespace:TxmlNs, out:TxmlNode)
Returns	The namespace node to use or Null.
Description	Find the right namespace value for this prefix.
Information	If needed create and add a new namespace decalaration on the node Handle namespace aliases and make sure the prefix is not NULL, this is needed for attributes. Parameters: curNode : the input node namespace : the namespace out : the output node (or its parent)

Method getSpecialNamespace:TxmlNs(curNode:TxmlNode, uri:String, prefix:String, out:TxmlNode)
Returns	The namespace node to use or Null.
Description	Find the right namespace value for this URI.
Information	If needed create and add a new namespace decalaration on the node. Parameters: curNode : the input node uri : the namespace URI prefic : the suggested prefix out : the output node (or its parent)

Method getTemplate:TxsltTemplate(node:TxmlNode, style:TxsltStylesheet)
Returns	The xslt Template or Null if not found.
Description	Finds the template applying to this node.
Information	If style is non-Null it means one needs to look for the next imported template in scope. Parameters: node : the node being processed style : the current style

Method initKeys(doc:TxsltDocument)

Description

Computes all the keys tables for the current input document.

Information

Should be done before global varibales are initialized.

Parameters:

doc : an XSLT document

Method needElemSpaceHandling:Int()
Returns	1 if space should be stripped, 0 if not.
Description	Checks whether that stylesheet requires white-space stripping.

Method registerPersistRVT:Int(rvt:TxmlDoc)
Returns	0 in case of success and -1 in case of error.
Description	Register the result value tree for destruction at the end of the processing.
Information	Parameters: rvt : a result value tree

Method registerTmpRVT:Int(rvt:TxmlDoc)
Returns	0 in case of success and -1 in case of error.
Description	Register the result value tree for destruction at the end of the context.
Information	Parameters: rvt : a result value tree

Method templateProcess:TxmlNode(node:TxmlNode)
Returns	The computed tree replacement.
Description	Process the given node and return the new string value.

Function newTransformContext:TxsltTransformContext(stylesheet:TxsltStylesheet, doc:TxmlDoc)
Returns	The new xsltTransformContext or Null in case of error.
Description	Create a new XSLT TransformContext.
Information	Parameters: stylesheet : a parsed XSLT stylesheet doc : the input document

Module Information

Version	1.01
License	MIT
Author	Daniel Veillard
Credit	Adapted for BlitzMax by Bruce A Henderson
Modserver	BRL
History	1.01
History	Updated to Libxslt 1.1.20
History	1.00 Initial Release (Libxslt 1.1.16)