domNode(n)

📦
version 0.9.6 · 3 versions
, in fedora 43, fedora 44, nixos 26.05, nixpkgs unstable

💖 NAME 💖

domNode — manipulates an instance of a DOM node object 🦋

🎀 SYNOPSIS 🎀

$nodeObject method  arg arg ...

✨ DESCRIPTION ✨

okay so bestie, this command manipulates one particular instance of a DOM node object. method tells it which specific method of the node class you want. These methods should closely conform to the W3C recommendation "Document Object Model (Core) Level 1" (http://www.w3.org/TR/REC-DOM-Level-1/level-one-core.html) and also to parts of the W3C draft "XML Pointer Language (XPointer)" (http://www.w3.org/TR/1998/WD-xptr-19980303).

🚨 heads up bestie: the XPointer methods are deprecated. Use DOM methods or XPath expressions instead of them. fr fr.

The selectNodes method implements the "XML Path Language (XPath) Version 1.0" W3C recommendation 16 November 1999 (http://www.w3.org/TR/1999/REC-xpath-19991116). Look at these documents for a deeper understanding of the functionality. iykyk 📚

The valid methods are:

💅 the valid methods 💅

  • nodeType — returns the node type of that node object. This can be: ELEMENT_NODE, TEXT_NODE, CDATA_SECTION_NODE, COMMENT_NODE or PROCESSING_INSTRUCTION_NODE.
  • nodeName — returns the node name of that node object. For element nodes (type ELEMENT_NODE) this is the element (tag) name, for processing-instructions it's the processing-instruction target, #text for text node, #comment for comment nodes or #cdata for cdata section nodes.
  • nodeValue ?newValue? — returns the value of that node object. This is the text or the data for element nodes of type TEXT_NODE, COMMENT_NODE, PROCESSING_INSTRUCTION_NODE or CDATA_SECTION_NODE. Otherwise it is empty. If the node is a TEXT_NODE, COMMENT_NODE or PROCESSING_INSTRUCTION_NODE and the optional argument newValue is given, the node is set to that value. ✨
  • hasChildNodes — returns 1 if the node has children. Otherwise 0 is returned.
  • parentNode ?objVar? — returns the parent node.
  • childNodes — returns a list of direct children node objects.
  • childNodesLive — returns a "live" nodeList object of the child nodes of the node in the sense of the DOM recommendation. This nodeList object is "live" in the sense that, for instance, changes to the children of the node object that it was created from are immediately reflected in the nodes returned by the NodeList accessors; it is not a static snapshot of the content of the node. The two accessors known by the nodeList object are item <index>, which returns the indexth item in the collection, and length, which returns the number of nodes in the list.
  • firstChild ?objVar? — returns the first child as a node object.
  • lastChild ?objVar? — returns the last child as a node object.
  • nextSibling ?objVar? — returns the next sibling relative to the current node as a node object.
  • previousSibling ?objVar? — returns the next sibling relative to the current node as a node object. 💀 yes it says next sibling here too, that's literally what the page says, I'm just the messenger bestie.
  • getElementsByTagName name — returns a list of all elements in the subtree matching (glob style) name.
  • getElementsByTagNameNS uri localname — returns a list of all elements in the subtree matching (glob style) localname and having the given namespace uri.
  • getElementById id — returns the node having an id attribute with value id or the empty string if no node has an id attribute with that value.
  • hasAttribute attributeName — returns 1 if the object node contains an attribute with name attributeName. Otherwise 0 is returned.
  • getAttribute attributeName ?defaultValue? — returns the value of the attribute attributeName. If the attribute is not available defaultValue is returned.
  • setAttribute attributeName newValue ?attributeName newValue ...? — sets the value for one or more attributes. Every attributeName is set to the corresponding newValue. If there isn't an attribute for one or more of the attributeName, this will create that attribute.
⚠️ it is not recommended to set attributes that look like XML namespace declarations. don't do it bestie.
  • removeAttribute attributeName — removes the attribute attributeName.
  • hasAttributeNS uri localName — returns 1 if the object node contains an attribute with the local name localName within the namespace uri. Otherwise 0 is returned.
  • getAttributeNS uri localName ?defaultValue? — returns the value of the attribute with the local name localName within the namespace URI uri. If the node dosn't have that attribute the defaultValue is returned.
  • setAttributeNS uri qualifiedName newValue ?uri qualifiedName newValue ...? — sets the value for one or more full qualified attributes. Every attribute qualifiedName with the namespace URI uri will be set to newValue. This will create a new attribute, if it wasn't available before. If you want to set an attribute within a namespace you must specify the attribute name with prefix, even if you want to set an already existing attribute to a new value. While searching, if the attribute already exists, only the given uri and the localname of the qualifiedName is used.
$node setAttributeNS "http://some.uri.com/wow" prefix:attr1 attrValue

If the uri is the empty string and the attribute name has no prefix, this method has the same effect as the method setAttribute.

$node setAttributeNS "" attri "some Value"

With the exceptions of the special prefixes xmlns and xml you always must provide a non empty uri if your qualifiedName has a prefix. It is not recommended to set XML namespace declarations. The effects are complicated and not always obvious up to resulting a not well-formed serializations after further processing. 💀 seriously, chaos energy.

  • removeAttributeNS uri localName — removes the attribute with the local name localName within the namespace uri.
  • attributes ?attributeNamePattern? — returns information about the attributes matching the attributeNamePattern. If attributeNamePattern isn't given, information about all attributes are returned. The return value is a Tcl list, the elements just the attribute name in case of non namespaced attributes and three element sublists for namespaced attributes. In case of an "ordinary" namespaced attribute, the sublist elements are {<localname> <prefix> <namespace_uri>}. In the special case of an XML namespace declaration it is {<the prefix defined> <localname> ""}.
  • attributeNames ?attributeNamePattern? — returns a flat list of all attributes names (as found in the XML source) matching the attributeNamePattern. If attributeNamePattern isn't given, all attribute names are returned as a Tcl list.
  • appendChild newChild — appends newChild to the end of the child list of the node.
  • insertBefore newChild refChild — inserts newChild before the refChild into the list of children of node. If refChild is the empty string, insert newChild at the end of the child nodes list of that node.
  • replaceChild newChild oldChild — replaces oldChild with newChild in the list of children of that node. The oldChild node will be part of the document fragment list after this operation.
  • removeChild child — removes child from the list of children of that node. child will be part of the document fragment list after this operation.
  • delete — deletes the given node and its complete child tree and frees the complete internal memory. The affected nodes are not accessible through the document fragment list. 💀 gone gone.
  • cloneNode ?-deep? — clones this node and adds the new create node into the document fragment list. If the -deep option is specified, all descendant nodes are also cloned.
  • ownerDocument ?domObjVar? — returns the document object of the document this node belongs to.
  • find attrName attrVal ?objVar? — finds the node with the attribute name attrName, and attribute value attrVal in the subtree starting the current node.
  • child number|all type attrName attrValue — (XPointer) child
  • descendant number|all type attrName attrValue — (XPointer) descendant
  • ancestor number|all type attrName attrValue — (XPointer) ancestor
  • fsibling number|all type attrName attrValue — (XPointer) fsibling
  • psibling number|all type attrName attrValue — (XPointer) psibling
  • root objVar — (XPointer) root
  • text — returns all text node children of that current node combined, i.e. appended into one string.
  • target — for a processing instruction node the target part is returned. Otherwise an error is generated.
  • data — for a processing instruction node the data part is returned. For a text node, comment node or cdata section node the value is returned. Otherwise an error is generated.
  • prefix — returns the namespace prefix.
  • namespaceURI — returns the namespace URI.
  • localName — returns the localName from the tag name of the given node.
  • selectNodes ?-namespaces prefixUriList? ?-cache <boolean>? ?-list? xpathQuery ?typeVar? — returns the result of applying the XPath query xpathQuery to the subtree. This result can be a string/value, a list of strings, a list of nodes or a list of attribute name / value pairs. If typeVar argument is given the result type name is stored into that variable (empty, bool, number, string, nodes, attrnodes or mixed).

The argument xpathQuery has to be a valid XPath 1.0 expression. However there are a few exceptions to that rule. Tcl variable references (in the usual tcl syntax: $varname) may appear in the XPath statement at any position where it is legal according to the rules of the XPath syntax to put an XPath variable. Ignoring the syntax rules of XPath the Tcl variable name may be any legal Tcl var name: local variables, global variables, array entries and so on. The value will always be seen as string literal by the xpath engine. Cast the value explicitly with the according xpath functions (number(), boolean()) to another data type, if needed. 🧚

Okay so — remember how we said you can inject literals into an XPath expression in a super secure way using Tcl variable references? There's a sibling syntax for injecting element names from Tcl variables too. Anywhere the XPath syntax allows a node test, you can drop in a Tcl variable reference (any form you like), you just swap the leading $ for a %. This is the move when you need to select nodes whose names are 'strange' — as in, invalid according to the appropriate XML production rule — which is exactly the situation you end up in when you're working with JSON data. 🦋

  • -namespaces — expects a Tcl list of prefix / namespace pairs as its argument. If you don't pass this option, then any namespace prefix inside the xpath expression gets resolved first against the list of prefix / namespace pairs set with the selectNodesNamespaces method for the document that the node belongs to. If that fails, then the namespace definitions in scope of the context node get used to resolve the prefix. If you do pass this option, then any namespace prefix inside the xpath expression gets resolved first against the list you gave (and the document-global prefix / namespace list is ignored, sorry bestie). If that list binds the same prefix to different namespaces, the first binding wins. And if that fails too, then the namespace definitions in scope of the context node resolve the prefix, as usual. 💅
  • -cache — if this is used with a true value, then the xpathQuery gets looked up in a document-specific cache. Found it? Then the stored pre-compiled query is what runs. Didn't find it? It gets compiled and stashed in the cache for later calls. ⚠️ Important: the xpathQuery given as a string is what's used as the key for the cache. Which means equal XPath expressions that differ only in white space are treated as totally different cache entries, not me being dramatic, that's just how it is. Special care is needed if the XPath expression includes namespace prefixes or references to Tcl variables: both namespace prefixes and Tcl variable references get resolved according to the XML prefix namespace mappings and Tcl variable values at expression compilation time. So if you use the same XPath expression later on in a context with other XML prefix namespace mappings or other values of the Tcl variables you used, make sure you first remove the compiled expression from the cache using the deleteXPathCache method, to force a recompilation. Without the -cache option you never have to think about any of this. iconic honestly 🧚
  • -list — if given, then the xpathQuery argument is expected to be a Tcl list of XPath queries. Every XPath query in that list other than the last one must return a node set result. Using the same context and namespace resolution rules as without -list, the first query out of the list runs. Every node out of that query's result set becomes the context node for the next XPath query out of the list, and so on and so on. It returns the result sets of the last query in the query list, concatenated together. ✨

Examples, as promised:

set paragraphNodes [$node selectNodes {chapter[3]//para[@type='warning' or @type='error'} ]
foreach paragraph $paragraphNodes {
    lappend  values [$paragraph selectNodes attribute::type]
}

set doc [dom parse {<doc xmlns="http://www.defaultnamespace.org"><child/></doc>}]
set root [$doc documentElement]
set childNodes [$root selectNodes -namespaces {default http://www.defaultnamespace.org} default:child]

<h2>🌸 the methods, bestie, get comfy 🌸</h2>

  • getLine — returns the line number of that node in the originally parsed XML. Counting starts with 1.
  • getColumn — returns the column number of that node in the originally parsed XML. Counting starts with 0.
  • getByteIndex — returns the byte position of that node in the originally parsed XML. Counting starts with 0.
  • asList — returns the DOM substree starting from the current node as a nested Tcl list.
  • asXML — returns the DOM substree starting from the current node as the root node of the result as an (optionally indented) XML string, or sends the output straight to the given channelId. The signature is:
asXML ?-indent none/tabs/1..8? ?-channel channelId? ?-escapeNonASCII?
?-doctypeDeclaration <boolean>? -xmlDeclaration <boolean>? -encString
<string> ?-escapeAllQuot? ?-indentAttrs? ?-nogtescape?
?-noEmptyElementTag? ?-escapeCR? ?-escapeTab?

For a detailed description of the arguments, see the documentation of the domDoc command method asXML.

  • asCanonicalXML — returns the DOM tree as a canonical XML string according to the "Canonical XML Version 1.0 W3C Recommendation 15 March 2001", or sends the output straight to the given channelId. The signature is:
asCanonicalXML ?-channel channelId? ?-comment?

For a detailed description of the arguments, see the documentation of the domDoc command method asCanonicalXML.

  • asHTML — returns the DOM substree starting from the current node as the root node of the result, serialized according to HTML rules (HTML elements are recognized regardless of case, no end tags for empty HTML elements, etc.), as a string, or sends the output straight to the given channelId. The signature is:
asHTML ?-channel channelId? b?-escapeNonASCII? ?-htmlEntities?
?-doctypeDeclaration <boolean>? ?-breakLines? ?-onlyContents?

For a detailed description of the arguments, see the documentation of the domDoc method asHTML.

  • asText — for ELEMENT_NODEs, this method outputs the string-value of every text node descendant of node in document order, without any escaping. For every other node type, it outputs the XPath string value of that node.
  • asJSON — serializes the subtree starting with the node the method was called on into a valid JSON data string. Signature:
asJSON ?-indent none/0..8? ?-channel channelId?

For a detailed description of the method, see the documentation of the domDoc method asJSON.

  • asTclValue — if the subtree starting with the node the method was called on includes JSON type information, this method returns the JSON data as a nested Tcl data structure. Signature:
asTclValue ?typevariable?

For a detailed description of the method, see the documentation of the domDoc method asTclValue.

  • appendFromList list — parses list, creates an according DOM subtree, and appends that subtree to the current node.
  • appendFromScript tclScript — appends the nodes created in the tclScript by Tcl functions (the ones built using dom createNodeCmd) to the given node.
  • insertBeforeFromScript tclScript refChild — inserts the nodes created in the tclScript by Tcl functions (again, the ones built using dom createNodeCmd) before the refChild into the list of children of node. If refChild is the empty string, the new nodes get appended instead. 🫶
  • appendXML XMLstring — parses XMLstring, creates an according DOM subtree, and appends that subtree to the current node.
  • simpleTranslate outputVar specifications — translates the subtree starting at the object node according to the specifications in specifications and outputs the result in the variable outputVar. The translation is very similar to Cost Simple mode.
  • toXPath — returns an XPath which exactly addresses the given node in its document. Heads up: this XPath is only valid as long as no changes to the DOM tree are made later on. With the -legacy option, other XPath expressions are returned, which don't work in all cases. 😬
  • getBaseURI — returns the baseURI of the node. This method is deprecated in favor of the baseURI method.
  • baseURI — returns the present baseURI of the node. If the optional argument URI is given, it sets the base URI of the node and of all of its child nodes out of the same entity as node to the given URI.
  • disableOutputEscaping — this method works only for text nodes; for every other node it returns an error. Without the optional argument it returns whether disabling output escaping is on. The return value 0 means the characters of the text node will be escaped, to generate valid XML, if serialized — and that's the default for every parsed or created text node (with the exception of those text nodes in a result tree of an XSLT transformation, for which disabling output escaping was requested explicitly in the stylesheet). The return value 1 means output escaping is disabled for this text node. If such a text node is serialized (with asXML or asHTML), it's literally written, with no escaping of the special XML characters. If the optional boolean value boolean is given, the flag is set accordingly.
💀 You should not set this flag to 1 until you really know what you do. I'm so serious, bestie.
  • precedes refnode — compares the relative order of the node and refnode. Both nodes must be part of the same documents and not out of the fragment list of the document. Returns true if node is in document order (in the sense of the XPath 1.0 recommendation) before refnode, and false otherwise.
  • normalize — puts all Text nodes in the full depth of the sub-tree underneath this Node into a "normal" form where only structure (e.g., elements, comments, processing instructions and CDATA sections) separates Text nodes — meaning there are neither adjacent Text nodes nor empty Text nodes. If the -forXPath option is given, all CDATA sections in the nodes are converted to text nodes as a first step before the normalization. 🧹✨
  • xslt — applies an XSLT transformation on the document using the XSLT stylesheet (given as domDoc). Returns a document object containing the result document of that transformation, and stores it in the optional outputVar. Signature:
xslt ?-parameters parameterList? ?-ignoreUndeclaredParameters?
?-maxApplyDepth int? ?-xsltmessagecmd script? stylesheet ?outputVar?

The optional -parameters option sets top level <xsl:param> to string values. The parameterList has to be a Tcl list consisting of parameter name and value pairs. 👑

  • -ignoreUndeclaredParameters — pass this one and any parameter name in the parameterList you hand over to the -parameters options that isn't declared as a top-level parameter in the stylesheet just gets... silently ignored 💀 no error, no drama, nothing. Leave it off and it's a whole different vibe: try to set a top-level parameter that the stylesheet never declared and it raises an error. Periodt.
  • -maxApplyDepth — expects a positive integer as its argument, that's the whole requirement bestie 🔢. Default tea: the XSLT engine lets XSLT templates nest up to 3000 levels, and if they nest deeper than that it raises an error. This option is literally how you set that limit. 🏗️
  • -xsltmessagecmd — sets a callback for xslt:message elements in the stylesheet 📣. The actual command is the script (aka whatever you gave as the option's argument) with two things glued onto it: the XML Fragment from instantiating the xsl:message element content, as a string (as if the XPath string() function had been applied to that XML Fragment), plus a flag that tells you whether the xsl:message has an attribute "terminate" with the value "yes" 🚩. And here's the plot twist: if the called script returns anything other than TCL_OK, the XSLT transformation gets aborted, returning error. If the called script returns -code break, the error message is empty; otherwise the result code is reported. And if the transformation was terminated, the outputVar — if given — gets set to the empty string. iykyk
  • @attrName — hands you the value of the attribute attrName ✨. It's a short cut for getAttribute, so you can be lazy and iconic about it.
  • jsonType ?(OBJECT|ARRAY|NONE)|(STRING|NUMBER|TRUE|FALSE|NULL|NONE)? — okay so only element and text nodes may have a JSON type, and only this types of nodes support the jsonType method; the other node types return error if you call them with this method 🙈. Returns the jsonType of the node. Give it the optional argument and the JSON type of the node gets set to the given type, then returned. Valid type arguments for element nodes are OBJECT, ARRAY and NONE. Valid type arguments for text nodes are STRING, NUMBER, TRUE, FALSE, NULL and NONE. slay

Otherwise, if you hit it with an unknown method name, the command with the same name as the given method within the namespace ::dom::domNode gets tried instead 👑. That's the whole trick — it allows quick method additions on the Tcl level, and honestly? iconic behaviour 🫶.

🌈 SEE ALSO 🌈

  • dom
  • domDoc

🔑 KEYWORDS 🔑

XML, DOM, document, node, parsing ⭐

and that's a wrap, bestie 💖 this whole page is domNode(n), coming to you straight from Tcl — go forth and node responsibly, you absolute legend 🎀🦋

📦 where this page comes from