Get definitions of any namespaces defined in this XML node

If the given node has any namespace definitions declared within it, i.e. of the form xmlns:myNamespace="http://www.myNS.org", xmlNamespaceDefinitions provides access to these definitions. While they appear in the XML node in the document as attributes, they are treated differently by the parser and so do not show up in the nodes attributes via xmlAttrs.

getDefaultNamespace is used to get the default namespace for the top-level node in a document.

The recursive parameter allows one to conveniently find all the namespace definitions in a document or sub-tree without having to examine the file. This can be useful when working with XPath queries via getNodeSet.

Usage

xmlNamespaceDefinitions(x, addNames = TRUE, recursive = FALSE, simplify = FALSE, ...)
xmlNamespaces(x, addNames = TRUE, recursive = FALSE,  simplify = FALSE, ...)
getDefaultNamespace(doc, ns = xmlNamespaceDefinitions(doc, simplify = simplify),  
                      simplify = FALSE)

Arguments

x

the XMLNode object in which to find any namespace definitions

addNames

a logical indicating whether to compute the names for the elements in the resulting list. The names are convenient, but one can avoid the (very small) overhead of computing these with this parameter.

doc

the XMLInternalDocument object obtained from a call to xmlParse

recursive

a logical value indicating whether to extract the namespace definitions for just this node (FALSE) or all of the descendant nodes as well (TRUE). If this is TRUE, all the namespace definitions are collected into a single "flat" list and so there may be duplicate names.

simplify

a logical value. If this is TRUE, a character vector of prefix-URI pairs is returned. This can be used directly in calls to functions such as xpathApply and getNodeSet. The default value of FALSE returns a list of name space definitions which also identify whether the definition is local to the particular node or inherited from an ancestor.

ns

the collection of namespaces. This is typically omitted but can be specified if it has been computed in an earlier step.

...

additional parameters for methods

Value

A list with as many elements as there are namespace definitions. Each element is an object of class XMLNameSpace, containing fields giving the local identifier, the associated defining URI and a logical value indicating whether the definition is local to this node. The name of each element is the prefix or alias used for that namespace definition, i.e. the value of the id field in the namespace definition. For default namespaces, i.e. those that have no prefix/alias, the name is "".

References

https://www.w3.org/XML/

Author

Duncan Temple Lang

See also

xmlTreeParse xmlAttrs xmlGetAttr

Examples

  f = system.file("exampleData", "longitudinalData.xml", package = "XML")
  n = xmlRoot(xmlTreeParse(f))
  xmlNamespaceDefinitions(n)
#> $rs
#> $id
#> [1] "rs"
#> 
#> $uri
#> [1] "http://www.omegahat.net/RSXML"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> $lgtdl
#> $id
#> [1] "lgtdl"
#> 
#> $uri
#> [1] "http://www.r-project.org/XML/lgtdl"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinitions"
  xmlNamespaceDefinitions(n, recursive = TRUE)
#> $rs
#> $id
#> [1] "rs"
#> 
#> $uri
#> [1] "http://www.omegahat.net/RSXML"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> $lgtdl
#> $id
#> [1] "lgtdl"
#> 
#> $uri
#> [1] "http://www.r-project.org/XML/lgtdl"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinitions"


    # Now using internal nodes.
  f = system.file("exampleData", "namespaces.xml", package = "XML")
  doc = xmlInternalTreeParse(f)
  n = xmlRoot(doc)
  xmlNamespaceDefinitions(n)
#> [[1]]
#> $id
#> [1] ""
#> 
#> $uri
#> [1] "http://www.omegahat.net"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> $omegahat
#> $id
#> [1] "omegahat"
#> 
#> $uri
#> [1] "http://www.omegahat.net"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> $r
#> $id
#> [1] "r"
#> 
#> $uri
#> [1] "http://www.r-project.org"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinitions"

  xmlNamespaceDefinitions(n, recursive = TRUE)
#> [[1]]
#> $id
#> [1] ""
#> 
#> $uri
#> [1] "http://www.omegahat.net"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> $omegahat
#> $id
#> [1] "omegahat"
#> 
#> $uri
#> [1] "http://www.omegahat.net"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> $r
#> $id
#> [1] "r"
#> 
#> $uri
#> [1] "http://www.r-project.org"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> $c
#> $id
#> [1] "c"
#> 
#> $uri
#> [1] "http://www.c.org"
#> 
#> $local
#> [1] TRUE
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinition"
#> 
#> attr(,"class")
#> [1] "XMLNamespaceDefinitions"