From: "David A. Black" <dblack@...>
Date: 2009-08-10T15:32:44+09:00
Subject: Re: How to define doubles: Array-to-hash

Hi --

On Mon, 10 Aug 2009, Bertram Scharpf wrote:

> Hi,
>
> Am Montag, 10. Aug 2009, 08:17:42 +0900 schrieb 7stud --:
>> Bertram Scharpf wrote:
>>>   h = Hash.new { |h,k| h[k] = 0 }
>>
>> h = Hash.new { |h,k| h[k] = 0 }
>>
>> is equivalent to:
>>
>> h = Hash.new(0)
>
> Arrgh. Of course.

Actually they're not equivalent.

>> h = Hash.new(0)
=> {}
>> h[1]
=> 0
>> h
=> {}
>> h = Hash.new {|h,k| h[k] = 0 }
=> {}
>> h[1]
=> 0
>> h
=> {1=>0}


David

-- 
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