From: ts <decoux@...>
Date: 2004-04-23T22:54:19+09:00
Subject: Re: find a best version (of a package)

>>>>> "s" == saiph  <excapersgarden@libero.it> writes:

s> vv = ['ruby-2.2.5', 'ruby-3.2.6', 'ruby-5']
s> i = vv.best_version?

s> how would you write or change this?

 Well, like said previously it's faster to do it if all your numbers have
 only one digit.

s> def newer?(s)
s> def best_version?

 generally a method with ? at the end, return true or false perhaps best to
 change the name.

 Something like this (not tested)

svg% cat b.rb
#!/usr/bin/ruby
class String
   REG = /\A\w+-(?=[\d.]+\z)/

   def newer(s)
      return nil unless self[REG] == s[REG]
      a = self.scan(/(\d+)\.?/).flatten
      b = s.scan(/(\d+)\.?/).flatten
      a.zip(b) do |x, y|
         t = x.to_i <=> y.to_i
         return t unless t.zero?
      end
      0
   end
end

class Array
   def best_version
      inject do |res, elem|
         t = res.newer(elem)
         return nil if t.nil?
         t>=0 ? res : elem
      end
   end
end
vv = ['ruby-2.2.5', 'ruby-3.2.6', 'ruby-5']
puts vv.best_version
svg%
 
svg% b.rb
ruby-5
svg% 



Guy Decoux