From: "David A. Black" <dblack@...>
Date: 2008-04-12T04:20:57+09:00
Subject: Re: delete_if, select and (lack of) delete_if!, self.POLS == false

Hi --

On Sat, 12 Apr 2008, Saku Ytti wrote:

> On (2008-04-12 04:04 +0900), Robert Dober wrote:
>
>> x=[*0..1]
>> x.select{|n| n.even?} -> [0]
>> x -> [0,1]
>> x.reject!{|n| n.odd?} -> [0]
>> x -> [0]
>
> Not sure what's going on there, but this looks correct to me:

select is selecting all the even ones, and reject! is rejecting all
the odd ones, and in both cases, you're seeing the results (the array
with only the even ones; the array without the odd ones). In the case
of reject! you're also seeing that the contents of the array have been
replaced with the results of the reject operation.

I think if you want a reject operation whose return value is the same
as a select operation, you'll probably need to come up with a new
method name :-)


David

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