From: Jason Lillywhite <jason.lillywhite@...>
Date: 2008-11-20T13:01:53+09:00
Subject: Re: build hash by iterating

Botp, thanks. That is an easier way to look at it. Can I go back to this 
Enumerable#inject? I understand iterating on elements of an array like 
this:

range = (1..4)
sum = range.inject(0) {|result, element| result += element }

#I understand inject to be doing this (where my 'i' means 'iteration'):
#sum(i=1) = 0 + 1 = 1
#sum(i=2) = sum(i=1)  + 2 = 3
#sum(i=3) = sum(i=2) + 3 = 6
#sum(i=4) = sum(i=3) + 4 = 10
=> sum = 10

#However, iterating over a hash is confusing me. Here is a simple 
example:

hash = [[:diameter, 45], [:id, 2]].inject({}) do |result, element|
  result[element.first] = element.last
  result
end

#can someone help me understand better what exactly is happening on each 
iteration?
#hash(i=1) = ??
#hash(i=2) = ??

Thank you!

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