From: "David A. Black" <dblack@...>
Date: 2009-07-22T04:26:05+09:00
Subject: Re: Mean method

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Hi --

On Wed, 22 Jul 2009, Brian Candler wrote:

> Älphä Blüë wrote:
>> From my understanding of inject, using above..
>>
>> a = first instance of array
>> b = subsequent instances of array
>
> No, not exactly. You are using the new 1.9 usage (possibly also 1.8.7):
>
>  foo.inject { |a,b| ... }
>
> a is the first element of the array in the first iteration only. For
> subsequent iterations, a is the value of the previous block evaluation.
>
> It may be clearer if you stick to the old usage:
>
>  foo.inject(init) { |a,b| ... }

You can do the no-arg version in 1.8.6 too:

$ ruby186 -e 'p [1,2,3].inject {|a,b| a + b }'
6


David

-- 
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