From: Rick DeNatale <rick.denatale@...>
Date: 2007-06-07T08:14:53+09:00
Subject: Re: code problems

On 6/6/07, Robert Dober <robert.dober@gmail.com> wrote:

>
> That is a good example I really like to build on it.
> Thanks.
>
> Maybe I might add one thing which took me some minutes to work out ;)
> the nil value for the cont variable comes from :   puts "After call".

Actually it comes from the puts "After callcc" as this change demonstrates;

rick@frodo:/public/rubyscripts$ cat testcontin.rb
def continuation
  puts "Before callcc"
  callcc {|lola| puts "In callcc";return lola}
  puts "After callcc"
  "returning"
end

puts "Begin"
cont = continuation
puts "Got cont #{cont.inspect}"
if cont
  cont.call
  puts "After call"
  "Hello"
end
puts "All done"
rick@frodo:/public/rubyscripts$ ruby testcontin.rb
Begin
Before callcc
In callcc
Got cont #<Continuation:0xb7d58768>
After callcc
Got cont "returning"
testcontin.rb:12: undefined method `call' for "returning":String (NoMethodError)

-- 
Rick DeNatale

My blog on Ruby
http://talklikeaduck.denhaven2.com/