From: Jim Freeze <jim@...>
Date: 2003-04-08T13:28:00+09:00
Subject: Re: Array Sutraction

On Tuesday,  8 April 2003 at 13:19:32 +0900, Yukihiro Matsumoto wrote:
> Hi,
> 
> In message "Array Sutraction"
>     on 03/04/08, Jim Freeze <jim@freeze.org> writes:
> 
> |So it would seem that Array#- is incomplete and the user
> |is required to apply #uniq to the result.
> 
> If you want uniq elements in the result.  1.8.0 Array#- removes
> elements in the right operand from the receiver (right operand).
> 
> 							matz.
 
 I'm sorry Matz, I don't understand.

 I don't have a horse in either the set or bag race.
 It's just the current implementation is very confusing.

 If I have a = [1,1,2,2,2] and I subtract [2], then
 I should get [1,1,2,2] if a is considered a bag.
 If a is considered a set, then it must first be
 temporarily converted to a set [1,2] and then
 the subtraction is performed yielding [1].

 However, 1.8.0 returns [1,1].

 ruby -ve 'p [1,1,2,2,2]-[2]'
 ruby 1.8.0 (2003-03-10) [i386-freebsd4.6]
 [1, 1]

-- 
Jim Freeze
----------
There's no real need to do housework -- after four years it doesn't get
any worse.