Ruby

I highlight below an aspect of a programming language that just assumes too much and is hard to make sense of.

require 'open-uri'
require 'redis'

URLS = %w[
    http://www.gutenberg.org/ebooks/98.txt.utf-8
    http://www.gutenberg.org/ebooks/1400.txt.utf-8
    http://www.gutenberg.org/ebooks/730.txt.utf-8
    http://www.gutenberg.org/ebooks/766.txt.utf-8
    http://www.gutenberg.org/ebooks/19337.txt.utf-8
    http://www.gutenberg.org/ebooks/700.txt.utf-8
]

BOOKS = URLS.map(&File.method(:basename))
REDIS = Redis.current

URLS.each do |url|
    text = open(url)
    name = File.basename(url)

    text.each_line do |line|
        REDIS.pfadd(name,line.split(/\s+/).map(&:downcase))
    end
end

BOOKS.each do |name|
    puts "#{name}: #{REDIS.pfcount(name)}"
end

puts "All: #{REDIS.pfcount(*BOOKS)}"