Update existing doc with REXML

[peri]

I have been searching around the forums and the documentation, but I
do not see any examples/topics on how to open an existing XML document
and update a value (element's text value, for example) using REXML.
Is it even possible? All I have for a workaround is overwriting the
existing file using document.write. Am I missing something obvious
here?

Below is an example I am trying to work with:
#===========================================
doc = Document.new File.read('cars.xml')

doc.root.each_element("//vehicle[make='Ford']") do |file_node|
file_node.elements['method'].text = "U"
end

File.open('cars.xml','w') do |f|
f.write doc.write
end

 

[bmunat]

Hmm, Document#write takes the output stream as an argument... so, I
think you want:

doc.write(f)

Hope that helps,

Ben