From: Robert Klemme <shortcutter@...>
Date: 2008-05-02T04:25:08+09:00
Subject: Re: Please explain nuances of ||=

On 01.05.2008 20:54, Simon Krahnke wrote:
> * David A. Black <dblack@rubypal.com> (18:56) schrieb:
> 
>> Hi --
>>
>> On Fri, 2 May 2008, Ruby Freak wrote:
>>
>>> I am reading some of the ruby files in rails and I an seeing the ||=
>>> method used a lot.
>>> knowing ruby the way I do, I realize that she has lots of magical
>>> surprises and I really want to get to know this girl!
>> x ||= y means:  x || x = y
> 
> No, it means: x = x || y

I believe you are wrong.

irb(main):001:0> h={}
=> {}
irb(main):002:0> h=Hash.new true
=> {}
irb(main):003:0> h[1]
=> true
irb(main):004:0> h[1] ||= 10
=> true
irb(main):005:0> h
=> {}
irb(main):006:0>

If you were right, h would look differently:

irb(main):008:0> h=Hash.new true
=> {}
irb(main):009:0> h[1] = h[1] || 10
=> true
irb(main):010:0> h
=> {1=>true}

The same topic has been discussed exhaustively a few days ago.

Cheers

	robert