Pulling text from elements with REXML

Ruby
1

Hi

I am using REXML to pull text from a NewsML document.

require ‘rexml/document’
include REXML
file = File.new(“Main_News.xml”)
doc = Document.new(file)
root = doc.root
puts
root.elements[“NewsItem/NewsComponent/NewsComponent[1]/NewsComponent/ContentItem/DataContent/nitf/body/body.head/hedline/hl1”]

Gives me…

Blueprint to cut emissions unveiled

Is there an easy way (ie something in REXML) to pull just the text
without the containers and .

Paul

2

Paul W. wrote:

root.elements[“NewsItem/NewsComponent/NewsComponent[1]/NewsComponent/ContentItem/DataContent/nitf/body/body.head/hedline/hl1”]

Gives me…

Blueprint to cut emissions unveiled

Is there an easy way (ie something in REXML) to pull just the text
without the containers and .

If I understood correctly, you need the text content of the node rather
than the whole node. This can be accomplished with:

some_element.text

so you could do something like

root.elements[…your stuff_here…].to_a.each {|e| puts e.text}

HTH,
Peter
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3

On Mar 19, 5:38 am, Paul W. [email protected] wrote:

root.elements[“NewsItem/NewsComponent/NewsComponent[1]/NewsComponent/Conten tItem/DataContent/nitf/body/body.head/hedline/hl1”]

Gives me…

Blueprint to cut emissions unveiled

Is there an easy way (ie something in REXML) to pull just the text
without the containers and .

require ‘rexml/document’
doc = REXML::Document.new(“hello world”)
p REXML::XPath.first( doc, ‘/root/kid/text()’ )
#=> “hello world”

4

On Mar 19, 8:04 am, “Phrogz” [email protected] wrote:

require ‘rexml/document’
doc = REXML::Document.new(“hello world”)
p REXML::XPath.first( doc, ‘/root/kid/text()’ )
#=> “hello world”

Also, depending on your needs:

include REXML
doc = Document.new(“helloworld”)
p XPath.match( doc, ‘/root/kid/text()’ )
#=> [“hello”, “world”]

5

Hey,

Two notes:

  1. I always suggest the REXML::XPath methods over the others for
    people who grok XPath.
  2. A REXML::XPath.* … text() match will return a REXML::Text node,
    which may not be what you want:

$ irb --simple-prompt foo.rb

require ‘rexml/document’
=> true

doc = REXML::Document.new(“hello world”)
=> … </>

REXML::XPath.first( doc, ‘/root/kid/text()’ )
=> “hello world”

REXML::XPath.first( doc, ‘/root/kid/text()’ ).class
=> REXML::Text

Just something to be aware of (use .to_s if you want a string, as
usual).

HTH,
Keith

6

Peter S. wrote:

If I understood correctly, you need the text content of the node rather
than the whole node. This can be accomplished with:

some_element.text

You did understand correctly, .text on the end was all I needed.

Cheers

Paul

7

require ‘rexml/document’
doc = REXML::Document.new(“hello world”)
p REXML::XPath.first( doc, ‘/root/kid/text()’ )
#=> “hello world”

Thanks for that, I’m now using REXML::XPath with a combination of .first
and .match to pull the element text out.

One more thing, given an XML document…

hello world

What would be the path to the attribute ‘stuff’ and return
‘some-other-text’?

Paul

8

On Mar 22, 10:44 am, Paul W. [email protected] wrote:

One more thing, given an XML document…

hello world

What would be the path to the attribute ‘stuff’ and return
‘some-other-text’?

require ‘rexml/document’
include REXML
doc = Document.new( <<ENDDOC )

hello world
hello world

ENDDOC

att = XPath.first( doc, ‘//kid/@stuff’ )
p att, att.class, att.value
#=> stuff=‘some-other-text’
#=> REXML::Attribute
#=> “some-other-text”

p XPath.first( doc, ‘//kid[@class=“best”]/@stuff’ ).value
#=> “gibbles”

I don’t know what the XPath syntax is to select the value of an
attribute directly. I’d be interested to know if someone else knows it.

9

Gavin K. wrote:

att = XPath.first( doc, ‘//kid/@stuff’ )

I don’t know what the XPath syntax is to select the value of an
attribute directly. I’d be interested to know if someone else knows it.

Cheers, it was the kid/@stuff I needed…

puts XPath.first( doc, ‘/root/kid/@stuff’ )

#=> some-other-text

Paul

10

On Mar 22, 11:02 am, Paul W. [email protected] wrote:

Gavin K. wrote:

att = XPath.first( doc, ‘//kid/@stuff’ )
I don’t know what the XPath syntax is to select the value of an
attribute directly. I’d be interested to know if someone else knows it.

Cheers, it was the kid/@stuff I needed…

puts XPath.first( doc, ‘/root/kid/@stuff’ )

#=> some-other-text

Nice, I didn’t realize that REXML::Attribute had such different output
for #inspect versus #to_s. It’s nice, then, that you don’t need to
call .value in this particular case. Just be aware that without
the .value call you still have an Attribute instance that can just be
treated as a string in some areas:

att = XPath.first( doc, ‘//kid/@stuff’ )

puts att
#=> some-other-text

puts att.value + ‘-more’
#=> some-other-text-more

puts att + “-more”
#=> tmp.rb:17: undefined method `+’ for
stuff=‘some-other-text’:REXML::Attribute (NoMethodError)