XML: print – R documentation

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print

Methods for displaying XML objects

Description

These different methods attempt to provide a convenient way to display R objects representing XML elements when they are printed in the usual manner on the console, files, etc. via the print function. Each typically outputs its contents in the way that they would appear in an XML document.

Usage

## S3 method for class 'XMLNode'
print(x, ..., indent= "", tagSeparator = "\n")
## S3 method for class 'XMLComment'
print(x, ..., indent = "", tagSeparator = "\n")
## S3 method for class 'XMLTextNode'
print(x, ..., indent = "", tagSeparator = "\n")
## S3 method for class 'XMLCDataNode'
print(x, ..., indent="", tagSeparator = "\n")
## S3 method for class 'XMLProcessingInstruction'
print(x, ..., indent="", tagSeparator = "\n")
## S3 method for class 'XMLAttributeDef'
print(x, ...)
## S3 method for class 'XMLElementContent'
print(x, ...)
## S3 method for class 'XMLElementDef'
print(x, ...)
## S3 method for class 'XMLEntity'
print(x, ...)
## S3 method for class 'XMLEntityRef'
print(x, ..., indent= "", tagSeparator = "\n")
## S3 method for class 'XMLOrContent'
print(x, ...)
## S3 method for class 'XMLSequenceContent'
print(x, ...)

Arguments

`x`	the XML object to be displayed
`...`	additional arguments for controlling the output from print. Currently unused.
`indent`	a prefix that is emitted before the node to indent it relative to its parent and child nodes. This is appended with a space at each succesive level of the tree. If no indentation is desired (e.g. when `xmlTreeParse` is called with `trim` and `ignoreBlanks` being `FALSE`) and `TRUE` respectively, one can pass the value `FALSE` for this `indent` argument.
`tagSeparator`	when printing nodes, successive nodes and children are by default displayed on new lines for easier reading. One can specify a string for this argument to control how the elements are separated in the output. The primary purpose of this argument is to allow no space between the elements, i.e. a value of `""`.

Value

Currently, NULL.

Note

We could make the node classes self describing with information about whether ignoreBlanks was TRUE or FALSE and if trim was TRUE or FALSE. This could then be used to determine the appropriate values for indent and tagSeparator. Adding an S3 class element would allow this to be done without the addition of an excessive number of classes.

Author(s)

Duncan Temple Lang

References

http://www.w3.org, http://www.omegahat.net/RSXML/

Examples

fileName <- system.file("exampleData", "event.xml", package ="XML")

     # Example of how to get faithful copy of the XML.
  doc = xmlRoot(xmlTreeParse(fileName, trim = FALSE, ignoreBlanks = FALSE))
  print(doc, indent = FALSE, tagSeparator = "")

     # And now the default mechanism
  doc = xmlRoot(xmlTreeParse(fileName))
  print(doc)

XML

Tools for Parsing and Generating XML Within R and S-Plus

v3.99-0.10

BSD_3_clause + file LICENSE

Authors

CRAN Team [ctb, cre] (de facto maintainer since 2013), Duncan Temple Lang [aut] (<https://orcid.org/0000-0003-0159-1546>), Tomas Kalibera [ctb]

Initial release