From: David Alan Black <dblack@...>
Date: 2002-01-25T02:16:56+09:00
Subject: Re: Serious Array Bug in Ruby 1.6.6?

Hello --

On Fri, 25 Jan 2002, William Djaja Tjokroaminata wrote:

[observation that Array.new(2, Hash.new) contains the same Hash twice]

> At least, probably the book should not give that example.  In the more
> general terms, probably Ruby should change the behavior of Array.new (n,
> Hash.new) as opposite to, say, Array.new (n, "A").  By having all the
> members refer to the same hash object, Ruby has violated the Priciple
> of Least Surprise.  Yes, probably it is more consistent in the way Ruby
> behaves currently.  However, when a person creates an array of hashes, I
> don't think there is anybody who wants all the hashes to refer to the same
> thing, because it is useless.

It's pretty easy and cheap (typing-wise) to do what you're aiming for:

  a = Array.new(2).map { Hash.new }
  # (or would map! be more logical and/or efficient there?)

so I'd tend not to see it as too desireable that the consistent
behavior of Array.new be changed.


David

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