From: "Brian F. Feldman" <green@...>
Date: 2001-01-08T04:45:31+09:00
Subject: [ruby-talk:8782] Re: No :<, :>, etc. methods for Array

gotoken@math.sci.hokudai.ac.jp (GOTO Kentaro) wrote:
> In message "[ruby-talk:8780] Re: No :<, :>, etc. methods for Array"
>     on 01/01/08, "Brian F. Feldman" <green@FreeBSD.org> writes:
> >class Array
> >    def sum
> >        total = self[0]	# defaults to nil
> >	self[1..-1].each {|x| total += x}
> >	total
> >    end
> >end
> >
> >It simplifies lots of things (especially mathematics) in Ruby to have it, 
> >and I believe it's generally useful enough that it should probably be 
> >standard.  What do you think?
> 
> See:
> http://www.rubycentral.com/faq/rubyfaq-11.html#ss11.4
> 
> `Enumerable#inject' is introduced there.  That may be adopted if an
> apter method name is proposed.

Except that I don't really ever see the need for the inject functionality 
itself.  A general sum method wouldn't prevent an inject method from being 
created, and I feel it's much more generally important (if it were in 
Enumerable, it feels natural next to min and max).

I know you can define sum in terms of inject, but what is the point of 
having inject if people are just going to use it to create sum?

-- 
 Brian Fundakowski Feldman           \  FreeBSD: The Power to Serve!  /
 green@FreeBSD.org                    `------------------------------'