From: Stefan Lang <perfectly.normal.hacker@...>
Date: 2008-03-08T08:07:53+09:00
Subject: Re: ActiveSupport Enumerable#sum should not use #size

2008/3/7, Drew Olson <olsonas@gmail.com>:
> Stefan Lang wrote:
>  > inject takes the identity as first parameter:
>  >
>  >     inject(identity) { |sum, element| sum + element }
>  >
>  > and since they define Symbol#to_proc, this can even be
>  >
>  >     inject(identity, &:+)
>  >
>  >>       end
>  >>     end
>  >>
>  >>  Look right?
>  >>
>  >>
>  >>  T.
>  >
>  > Stefan
>
>
> This is very concise, but doesn't have the same behavior as the original
>  sum. This will start any sum with the identity and then build on it from
>  there. Not that this is incorrect behavior, it's just different from
>  what was originally defined. For example:
>
>  a = [1,2,3]
>
>  original sum, with identity = 10, would return 6, whereas your version
>  would return 16.
>
>  - Drew

Hm, right. I find the name "identity" misleading in this case.

Stefan