From: Robert Dober <robert.dober@...>
Date: 2008-04-12T02:05:21+09:00
Subject: Re: delete_if, select and (lack of) delete_if!, self.POLS == false

On Fri, Apr 11, 2008 at 6:36 PM, David A. Black <dblack@rubypal.com> wrote:
> Hi --
>
>
>  On Sat, 12 Apr 2008, ara.t.howard wrote:
>
>
> >
> > On Apr 11, 2008, at 10:26 AM, Saku Ytti wrote:
> >
> > > Hey everyone,
> > >
> > > I was looking today for version of Array#select that would mutate the
> array
> > > by deleting selected elements from it.
> > > I first looked at delete_if, then noticed that it actually mutates
> original
> > > array and returns mutated array. I wonder would it make sense for
> delete_if
> > > not to mutate and return new array and delete_if! to mutate and return
> deleted
> > > elements?
> > >
> > > Of course what I want is simple method to implement, it just seems
> pretty
> > > typical desire for Array#select usage cases and also perhaps mutating
> > > delete_if is as well bit unexpected? Problem is, suggested change would
> > > break many current delete_if usage cases.
> > >
> >
> > a non-mutating delete_if is already there:
> >
> > array.select{|element| not orginal_condition(element)}
> >
> > ie
> >
> > odds = [0,1,2,3].select{|i| not i.even?}
> >
>
>  Also:
>
>   odds = [0,1,2,3].reject {|i| i.even? }
I guess even I could come up with an odd solution. (t'is 1 funny maybe?)
R.
-- 
http://ruby-smalltalk.blogspot.com/

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