From: ara howard <ara.t.howard@...>
Date: 2008-02-29T09:13:56+09:00
Subject: Re: Named sprintf parameters


On Feb 28, 2008, at 1:09 PM, yermej wrote:

> On Feb 28, 11:29 am, ara howard <ara.t.how...@gmail.com> wrote:
>
>> class String
>>   module M
>>     def % *args
>>       newstuff
>>       super
>>     end
>>   end
>>   include M
>> end
>>
>
> Can you please explain this? It looks to me like it would allow you to
> override a method, but still call the original without using alias.
> However, when I try anything like that, it only calls the original
> method. The method defined inside of M isn't called. Is that a 1.9
> thing or am I misunderstanding what you meant?
>

i was just being stupid.  you'd need something like this


cfp2:~ > cat a.rb
class String

   Percent = instance_method '%' unless defined? Percent

   def % *a, &b
     a.flatten!
     string =
       case a.last
         when Hash
           expand a.pop
         else
           self
       end
     if a.empty?
       string
     else
       Percent.bind(string).call(*a, &b)
     end
   end

   def expand! vars = {}
     loop do
       changed = false
       vars.each do |var, value|
         var = var.to_s
         var.gsub! %r/[^a-zA-Z0-9_]/, ''
         [
           %r/\$#{ var }\b/,
           %r/\@#{ var }\b/,
           %r/\$\{\s*#{ var }\s*\}/,
           %r/\@\{\s*#{ var }\s*\}/,
         ].each do |pat|
           changed = gsub! pat, "#{ value }"
         end
       end
       break unless changed
     end
     self
   end

   def expand opts = {}
     dup.expand! opts
   end

end

puts( 'I am @name'.expand(:name => 'Ara') )
puts( 'I am @name' % {:name => 'Ara'} )



cfp2:~ > ruby a.rb
I am Ara
I am Ara

a @ http://codeforpeople.com/
--
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h.h. the 14th dalai lama