From: Eric Mahurin <eric_mahurin@...>
Date: 2005-05-23T11:56:09+09:00
Subject: Re: join not in Enumerable

--- "David A. Black" <dblack@wobblini.net> wrote:
> Size has the other problem too: being enumerable does not
> mean being
> measurable.  For example:
> 
>    class C
>      include Enumerable
>      def each
>        loop { yield rand(100) }
>      end
>    end
> 
> It's meaningless to talk about the size of a C object -- but
> it's a
> perfectly legitimate enumerable.

I don't think an inifinite collection is a legitimate
enumerable.  Since each is an infinite loop, none of the
Enumerable methods will necessarily escape that loop. 
Enumerable#find (and friends) may return if it finds a match
since it probably breaks from the loop, but I don't think you
should depend on the implementation breaking from the loop (it
could simply record the first match).

I still think that any array method that is read-only and
operates in a single forward pass over an array would be good
to consider to go into Enumerable (Enumerable#sort* doesn't
meet those qualifications and I don't think it should have been
in there in the first place).  But, even without doing this
enum.to_a.<array_method> should work just fine.



		
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