From: Matthew Kerwin <matthew@...>
Date: 2012-09-13T11:30:03+09:00
Subject: Re: Breaking Down the Block

`my_array.inject(0) {|t,n| t + n}` basically breaks down like:

    t = 0
    my_array.each {|n| t = (t + n) }
    t

Similary, leaving out the inital value, `my_array.inject {|t,n| t +
n}` basically breaks down like:

    t = my_array[0]
    my_array[1..-1].each {|n| t = (t + n) }
    t

What you called 't' (often called the 'memory') is the accumulation,
or the result of the last iteration of the block.

On 13 September 2012 12:09, incag neato <lists@ruby-forum.com> wrote:
> Can someone please explain in plain english how this block treats the
> given variables (and values in the array)? I am struggling to understand
> the relationship of 't' and 'n' with the array.
>
> class Array
>   def sum
>     inject(0) {|t,n| t + n}
>   end
> end
> puts [1,2,3].sum
>
> Is 't' effectively labeled as '0' (zero), given the assignment on the
> inject method?
> What "is" 't' exactly?
>
> --
> Posted via http://www.ruby-forum.com/.
>



-- 
  Matthew Kerwin, B.Sc (CompSci) (Hons)
  http://matthew.kerwin.net.au/
  ABN: 59-013-727-651

  "You'll never find a programming language that frees
  you from the burden of clarifying your ideas." - xkcd