From: "Ara.T.Howard" <ahoward@...>
Date: 2003-11-17T10:29:13+09:00
Subject: Re: General Purpose Transactions

On Fri, 14 Nov 2003, T. Onoma wrote:

> Date: Fri, 14 Nov 2003 09:30:26 +0900
> From: T. Onoma <transami@runbox.com>
> Newsgroups: comp.lang.ruby
> Subject: General Purpose Transactions
> 
> I was writing a piece a code where I needed to change a few object attributes, call a method, then reset those attributes to what they were. And it occured to me that it might be nice to have general purpose tranactions.
> 
> 
> anobject = AClass.new
> anobject.attrib = 'set'
> transaction do
>   anobject.attrib = 'temp'
>   anobject.amethod
> end
> p anobject.attrib # => 'set'
> 
> 
> Seems like there may already be a simple way to do this, but it's not coming to mind.

austin's transaction::simple (RAA) does this.  also, there's always:

  begin
    org = obj and obj = Marshal.load(Marshal.dump(obj))
    obj.parm = 42
    obj.method()
  ensure
    obj = org
  end

-a
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