Running examples in ‘XML-Ex.R’ failed
The error most likely occurred in:

> base::assign(".ptime", proc.time(), pos = "CheckExEnv")
> ### Name: readHTMLTable
> ### Title: Read data from one or more HTML tables
> ### Aliases: readHTMLTable readHTMLTable,character-method
> ###   readHTMLTable,HTMLInternalDocument-method
> ###   readHTMLTable,XMLInternalElementNode-method
> ###   coerce,character,FormattedInteger-method
> ###   coerce,character,FormattedNumber-method
> ###   coerce,character,Percent-method coerce,character,Currency-method
> ###   FormattedInteger-class FormattedNumber-class Percent-class
> ### Keywords: IO data
> 
> ### ** Examples
> 
> ## Not run: 
> ##D ## This changed to using https: in June 2015, and that is unsupported.
> ##D # u = "http://en.wikipedia.org/wiki/World_population"
> ##D  u = "https://en.wikipedia.org/wiki/List_of_countries_and_dependencies_by_population"
> ##D 
> ##D  tables = readHTMLTable(u)
> ##D  names(tables)
> ##D 
> ##D  tables[[2]]
> ##D   # Print the table. Note that the values are all characters
> ##D   # not numbers. Also the column names have a preceding X since
> ##D   # R doesn't allow the variable names to start with digits.
> ##D  tmp = tables[[2]]
> ##D 
> ##D 
> ##D    # Let's just read the second table directly by itself.
> ##D  doc = htmlParse(u)
> ##D  tableNodes = getNodeSet(doc, "//table")
> ##D  tb = readHTMLTable(tableNodes[[2]])
> ##D 
> ##D   # Let's try to adapt the values on the fly.
> ##D   # We'll create a function that turns a th/td node into a val
> ##D  tryAsInteger = function(node) {
> ##D                   val = xmlValue(node)
> ##D                   ans = as.integer(gsub(",", "", val))
> ##D                   if(is.na(ans))
> ##D                       val
> ##D                   else
> ##D                       ans
> ##D                 }
> ##D 
> ##D  tb = readHTMLTable(tableNodes[[2]], elFun = tryAsInteger)
> ##D 
> ##D  tb = readHTMLTable(tableNodes[[2]], elFun = tryAsInteger,
> ##D                        colClasses = c("character", rep("integer", 9)))
> ## End(Not run)
> 
> zz =
+   readHTMLTable("https://www.inflationdata.com/Inflation/Consumer_Price_Index/HistoricalCPI.aspx")
Warning: XML content does not seem to be XML: 'https://www.inflationdata.com/Inflation/Consumer_Price_Index/HistoricalCPI.aspx'
> if(any(i <- sapply(zz, function(x) if(is.null(x)) 0 else ncol(x)) == 14)) {
+   # guard against the structure of the page changing.
+     zz = zz[[which(i)[1]]]  # 4th table
+     # convert columns to numeric.  Could use colClasses in the call to readHTMLTable()
+     zz[-1] = lapply(zz[-1], function(x) as.numeric(gsub(".* ", "", as.character(x))))
+     matplot(1:12, t(zz[-c(1, 14)]), type = "l")
+ }
> 
> 
> # From Marsh Feldman on R-help, possibly
> # https://stat.ethz.ch/pipermail/r-help/2010-March/232586.html
> # That site was non-responsive in June 2015,
> # and this does not do a good job on the current table.
> 
> doc <- "http://www.nber.org/cycles/cyclesmain.html"
> # The  main table is the second one because it's embedded in the page table.
> tables <- getNodeSet(htmlParse(doc), "//table")
Error in UseMethod("xmlNamespaceDefinitions") : 
  no applicable method for 'xmlNamespaceDefinitions' applied to an object of class "NULL"
Calls: getNodeSet ... xpathApply.XMLInternalDocument -> getDefaultNamespace -> xmlNamespaceDefinitions
Execution halted