From: dblack@...
Date: 2003-04-27T02:21:27+09:00
Subject: Re: Hashes and Enumerable#each_with_index

Hi --

On Sun, 27 Apr 2003, Sam Roberts wrote:

> Quoteing rpav@nwlink.com, on Fri, Apr 25, 2003 at 07:26:01AM +0900:
> > OK, looking at the archives I know this was discussed a few years ago,
> > but there seems to be no real conclusion or improvement since then.
> >
> > The problem:  Hash#each_with_index returns an index that is not usable
> > to address the hash.  That is, given the following:
> >
> >     h = Hash.new
> >     h.each_with_index {
> >         | o, i |
> >         ...
> >     }
> >
> > i is not defined such that h[i] == o, which is both misleading and
> > seemingly useless.  (This behavior, as per the previous discussion, can
> > be achieved with h.to_a.each_with_index.)
>
> This function already exists, for a Hash its called Hash#each.

Not exactly: Hash#each returns [k,v] pairs, not [v,k] pairs.  The
[element,index] style of Array#each_with_index is more similar to
the latter than the former (i.e., array[index] == element, and
hash[k] = v).


David

-- 
David Alan Black
home: dblack@superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav