From: Martin Bonner <marty@...>
Date: 2003-04-09T00:57:45+09:00
Subject: Re: Array Sutraction

----- Original Message -----
From: "Jim Freeze" <jim@freeze.org>

| On Tuesday,  8 April 2003 at 22:59:50 +0900, Michael Campbell wrote:
| > >
| > > I don't find this confusing. In fact I find the implicit
| > > application of
| > > uniq (older version) more confusing because it is somewhat
| > > surprising - at
| > > least to me.  In that case substraction indeed combines two
| > > operations.
| > >
| > > I'd view the substraction "a-b" as "remove all elements in b from
| > > a",
| > > which would reasonable lead to all 2's removed from [1,1,2,2,2]
| > > yielding
| > > [1,1].
| >
| >
| > So [1, 1, 2, 2] - [2] should yield the same as [1, 1, 2, 2] - [2, 2]?
| >  That seems odd to me.
|
| Yes. It's not really subtraction as implied by the '-' minus operator.
| Maybe it should be renamed to #remove_all_from. :)

Hmm.. there might still be some confusion there. I might expect that to
remove all elements from the array. Perhaps it should be called
#remove_all_elements_equivalent_to **
:)

Marty

** This was funny when I thought of it, but Austin, Texas has more than its
share of allergens in the air right now, so my head feels rather like a
recently kicked (US)football.

| --
| Jim Freeze
| ----------
| F: When into a room I plunge, I
| Sometimes find some VIOLET FUNGI.
| Then I linger, darkly brooding
| On the poison they're exuding.
| -- The Roguelet's ABC