From: Tammo Tjarks <tammo@...>
Date: 2008-05-25T05:54:22+09:00
Subject: Re: lambda, ->, haskell, and so on

I am not sure if that fits to the thread. I have not used yet the more 
sophisticated features of ruby. I like it mostly because I sometimes get the 
impression that it can read my mind ;). I like especially the iterators and 
blocks. Therefore my question. With respect to the question  how to  provide 
several blocks to a method. Is it possible to implement something like that:
a = Example.new
a.cond_each [{|a| a%2==0}, { 'even'},{|c| "it is #{c}"}]

Then the blocks could maybe adressed like that:
class Example < Array
  def cond_each
     each {|arrel| 
         if yield[0] arrel then
            yield[1]
         else
            yield[2] arrel
         end 
     }
  end
end
 
would be something like that possible for the parser? Is that a already an 
existing idea or maybe even somewhere implemented?

Tammo

Am Freitag, 23. Mai 2008 schrieb Nikolai Weibull:
> 2008/5/23  <Nate_Wiger@playstation.sony.com>:
> >    # Use coupled {{ }}
> >    named_scope :recent, {{|time = 2.weeks.ago| {:conditions =>
> >     ["released_at > ?", time]} }}
>
> What I don't quite understand is why we can't have multiple blocks to
> a method.  All but the last would be converted to anonymous functions
> that become normal parameters and the last would be a block that can
> be yielded to as before.  I just read
> http://pragdave.blogs.pragprog.com/pragdave/2008/05/new-lambda-synt.html
> and I'd prefer
>
> a = 0
> my_while { a < 5 }  do
>    puts a
>    a += 1
> end
>
> over
>
> a = 0
> my_while -> { a < 5 }  do
>    puts a
>    a += 1
> end
>
> (And I'd prefer 5.times{ |a| puts a } over both alternatives.)