From: "David A. Black" <dblack@...>
Date: 2009-02-12T10:28:17+09:00
Subject: Re: Array#to_hash

Hi --

On Thu, 12 Feb 2009, William James wrote:

> Trans wrote:
>
>> Would any problems arise from extending Array with this?
>>
>>   # Convert an array into an indexed hash.
>>   #
>>   # [:a,:b,:c].to_hash  #=> {0=>:a,1=>:b,2=>:c}
>>   #
>>   def to_hash
>>     h = {}
>>     each_with_index do |v, i|
>>       h[i] = v
>>     end
>>     h
>>   end
>>
>> Thanks,
>> T.
>
> Always remember:
>
> "We don't need no stinkin' loops!"
>
> a=[:a,:b,:c]
>    ==>[:a, :b, :c]
> Hash[ *(0...a.size).zip(a).flatten ]
>    ==>{0=>:a, 1=>:b, 2=>:c}

You'd want to use flatten(1) so as to avoid over-flattening.
(Available as the flatten_x extension for 1.8.6.)


David

-- 
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