From: Daniel Lucraft <dan@...>
Date: 2007-08-20T18:57:00+09:00
Subject: Re: Named Constructor Idiom in Ruby?

Arlen Christian Mart Cuss wrote:
> lost hold of the thought of how -- is there a straight-forward/neat way
> to do the named constructor idiom in Ruby?

You have some good answers, but here is yet another way that is quite 
interesting:

class A
  class << self; private :new; end

  def self.something
    a = self.allocate
    # set up a somehow
    a
  end

  def self.otherthing
    a = self.allocate
    # set up a somehow
    a
  end
end

allocate is like new but without calling initialize. I believe that new 
is basically defined as: (1) allocate, (2) initialize.

The only benefit of this over the other solutions is that it avoids 
calling new altogether. I have found this useful in a case where the new 
was very generalized and therefore slow.

best,
Dan
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