Running examples in 'selectr-Ex.R' failed
The error most likely occurred in:

> ### Name: querySelectorAll
> ### Title: Find nodes that match a group of CSS selectors in an XML tree.
> ### Aliases: querySelector querySelectorAll querySelectorNS
> ###   querySelectorAllNS
> 
> ### ** Examples
> 
>   hasXML <- require(XML)
Loading required package: XML
>   hasxml2 <- require(xml2)
Loading required package: xml2
Error: package or namespace load failed for 'xml2' in library.dynam(lib, package, package.lib):
 DLL 'Rcpp' not found: maybe not installed for this architecture?
> 
>   if (!hasXML && !hasxml2)
+     return() # can't demo without XML or xml2 packages present
> 
>   parseFn <- if (hasXML) xmlParse else read_xml
>   # Demo for working with the XML package (if present, otherwise xml2)
>   exdoc <- parseFn('<a><b class="aclass"/><c id="anid"/></a>')
>   querySelector(exdoc, "#anid")   # Returns the matching node
<c id="anid"/> 
>   querySelector(exdoc, ".aclass") # Returns the matching node
<b class="aclass"/> 
>   querySelector(exdoc, "b, c")    # First match from grouped selection
<b class="aclass"/> 
>   querySelectorAll(exdoc, "b, c") # Grouped selection
[[1]]
<b class="aclass"/> 

[[2]]
<c id="anid"/> 

attr(,"class")
[1] "XMLNodeSet"
>   querySelectorAll(exdoc, "b")    # A list of length one
[[1]]
<b class="aclass"/> 

attr(,"class")
[1] "XMLNodeSet"
>   querySelector(exdoc, "d")       # No match
NULL
>   querySelectorAll(exdoc, "d")    # No match
list()
attr(,"class")
[1] "XMLNodeSet"
> 
>   # Read in a document where two namespaces are being set:
>   # SVG and MathML
>   svgdoc <- parseFn(system.file("demos/svg-mathml.svg",
+                                 package = "selectr"))
>   # Search for <script/> elements in the SVG namespace
>   querySelectorNS(svgdoc, "svg|script",
+                   c(svg = "http://www.w3.org/2000/svg"))
<script type="application/ecmascript" xlink:href="test2.svg.coords.js"/> 
>   querySelectorAllNS(svgdoc, "svg|script",
+                      c(svg = "http://www.w3.org/2000/svg"))
[[1]]
<script type="application/ecmascript" xlink:href="test2.svg.coords.js"/> 

[[2]]
<script type="application/ecmascript" xlink:href="test2.svg.convert.js"/> 

attr(,"class")
[1] "XMLNodeSet"
>   # MathML content is *within* SVG content,
>   # search for <mtext> elements within the MathML namespace
>   querySelectorNS(svgdoc, "math|mtext",
+                   c(math = "http://www.w3.org/1998/Math/MathML"))
<mtext mathvariant="sans-serif">a</mtext> 
>   querySelectorAllNS(svgdoc, "math|mtext",
+                      c(math = "http://www.w3.org/1998/Math/MathML"))
[[1]]
<mtext mathvariant="sans-serif">a</mtext> 

[[2]]
<mtext mathvariant="sans-serif">b</mtext> 

attr(,"class")
[1] "XMLNodeSet"
>   # Search for *both* SVG and MathML content
>   querySelectorAllNS(svgdoc, "svg|script, math|mo",
+                      c(svg = "http://www.w3.org/2000/svg",
+                        math = "http://www.w3.org/1998/Math/MathML"))
[[1]]
<mo>+</mo> 

[[2]]
<script type="application/ecmascript" xlink:href="test2.svg.coords.js"/> 

[[3]]
<script type="application/ecmascript" xlink:href="test2.svg.convert.js"/> 

attr(,"class")
[1] "XMLNodeSet"
> 
>   if (!hasXML)
+     return() # already demo'd xml2
> 
>   # Demo for working with the xml2 package
>   exdoc <- read_xml('<a><b class="aclass"/><c id="anid"/></a>')
Error in read_xml("<a><b class=\"aclass\"/><c id=\"anid\"/></a>") : 
  could not find function "read_xml"
Execution halted