From: "Brian Schröder" <ruby.brian@...>
Date: 2005-09-01T19:05:24+09:00
Subject: Re: implementing the "each" method for own classes

On 01/09/05, Philipp Huber <huber.philipp@gmail.com> wrote:
> actually i did test it with a queue filled with a few elements. as you
> said the condition for the while loop should be testet at the
> beginning, otherwise nil could be returned.
> so my code looks like this:
> 
> def each
>   node=@head
>   while node=node.next
>    yield node.content
>   end
> end
> 
> do you have an example for the second remark, as i don't quite
> understand what you mean
> 
> thanks,
> philipp
> 
> 

Sorry for posting something that untested. But as I look again you
continue to have bugs in your code.

You are missing the first element. The following should work and also
return self. That allows you to do something like the following:

queue.each do | element | element.seen += 1 end.each do | element |
puts element end

Beware that the above example does not make that much sense, but I do
not have a better example ready.

def each
  node=@head
  while node
    yield node.content
    node=node.next
  end
  self
end

hope to help

Brian

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