From: Robert Klemme <shortcutter@...>
Date: 2013-02-15T02:04:23+09:00
Subject: Re: Best DRY way to write bang versions of methods?

On Thu, Feb 14, 2013 at 1:43 PM, Edoardo Rossi <edd.rossi@gmail.com> wrote:
> IMHO sometimes this is useful:
>
> def foo(something)
>   dup.foo!(something)
> end
>
> def foo!(something)
>   # do the work...
> end

There is one gotcha in this code: foo! will often return nil if
nothing is changed.  A better approach is

def foo(something)
  dup.tap {|copy| copy.foo!(something)}
end

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/