From: "David A. Black" <dblack@...>
Date: 2004-09-20T01:34:50+09:00
Subject: Re: Array#index block and rdetect

Hi --

On Sun, 19 Sep 2004, trans.  (T. Onoma) wrote:

> Couldn't the index of a hash be considered the key? So the block of #index 
> when applied is the value. i.e.

That's how I tend to see it, though Ruby has two interpretations of
"index" for hashes:

  irb(main):007:0> h = Hash[*%w{a b c d}]
  => {"a"=>"b", "c"=>"d"}
  irb(main):008:0> h.index("d")
  => "c"
  irb(main):009:0> h.each_with_index {|e,i| p i if e[0] == "c"}
  1

This is one of the reasons I've always felt that Hash#each_with_index
should be eliminated.  The "index" in h.each_with_index is not the
same as the "index" of h.index.  h.each_with_index is effectively
equivalent to h.to_a.each_with_index, but with the to_a being hidden.  


David

-- 
David A. Black
dblack@wobblini.net