Can you provide examples of parsing HTML?

Question

How do you parse HTML with a variety of languages and parsing libraries?

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When answering:

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Answer 1

language: Ruby
library: Hpricot

#!/usr/bin/ruby

require 'hpricot'

html = ''
['foo', 'bar', 'baz'].each {|link| html += "#{link}" }
html += ''

doc = Hpricot(html)
doc.search('//a').each {|elm| puts elm.attributes['href'] }