Why are there blank nodes/attributes when using LibXML Ruby?

Question

Using the Gem libxml-ruby, when we parse XML like so:

document = LibXML::XML::Parser.string( xmlData ).parse
for n in document.root.children
  # Do something
end

What we actually get is something like this:

root
-node empty
-node with data
-node empty

Same thing with attributes, there's a blank one padding between those we actually care about. What we end up needing to use is :options => LibXML::XML::Parser::Options::NOBLANKS

Why? :(

score 0 · Accepted Answer · answered Jul 24 '12 at 22:03

0

(Not necessarily an answer, but need formatting.)

What does the XML look like?

This XML:

<baz>
  <plugh>ohai</plugh>
</baz>

may contain whitespace text nodes for the CR/LF and indentation between the <baz> and <plugh> opening tags, and the same for between the closing tags. This may or may not be significant whitespace depending on the nature of the XML. Structurally, it's different than:

<baz><plugh>ohai</plugh></baz>

answered Jul 24 '12 at 22:03

Dave Newton

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Dave, your hunch was right! It seems the blank node is created if there is a space between the tags. ` ` gives me blank nodes but `` does not. – Clucking Turtle Jul 25 '12 at 15:06
@GeorgeChen Yeah, the whitespace text nodes have caught me out as well. – Dave Newton Jul 25 '12 at 15:09
PS: You can use `each_element()` to traverse only element children. – l0b0 Jan 21 '13 at 13:53

Why are there blank nodes/attributes when using LibXML Ruby?

1 Answers1