os.rb

data = <<TEXT
Lion (10.7.1)
Mac OS
Mac osx 
Windows 7
Mac osx, leopard
Linux
OSX
OSX
Mac OSX (snow leopard)
OSX
OSX
OSX Lion
OS X 10.7.1
OSX Lion
osx
Snow Leopard/Lion
Windows 7
Windows 7
Windows 7
Snow Leopard
Mac 0S 10.6
Mac OS X 10.6.8
Mac OS X v. 10.6.8
OSX 10.5.8
TEXT

hist = {}
data.split("\n").each do |os|
  os = os.strip.
    gsub("Lion (10.7.1)", "OSX 10.7").
    gsub("Mac OSX (snow leopard)", "OSX 10.6").
    downcase.
    gsub("mac osx, leopard", "OSX 10.5").
    gsub("mac 0s", "OSX").

    gsub(/(osx ?)*lion/i, "OSX 10.7").
    gsub(/(osx ?)*snow leopard/i, "OSX 10.6").
    gsub(/(osx ?)*leopard/i, "OSX 10.5").
    gsub(/(osx ?)*tiger/i, "OSX 10.4").
    gsub(/(mac ?)*os ?x?/i, 'OSX').
    gsub(/((mac ?)osx ?)+ */, "OSX ").
    
    gsub(/v\. ?/, '').
    gsub(/(10\.\d)\.\d/, '\\1').
    strip
  hist[os] ||= 0
  hist[os] += 1
end
require "awesome_print"
ap Hash[hist.sort]


=begin
If it starts with 10.7, you have Lion.
If it starts with 10.6, you have Snow Leopard.
If it starts with 10.5, you have Leopard.
If it starts with 10.4, you have Tiger.
If it starts with 10.3, you have Panther.
=end