From: Shyouhei Urabe <shyouhei@...>
Date: 2012-03-08T19:09:46+09:00
Subject: [ruby-core:43139] [ruby-trunk - Feature #4514] #deep_clone and #deep_dup for Objects


Issue #4514 has been updated by Shyouhei Urabe.


Some thoughts

* #deep_merge is a Rails method.  If you only need Arrays + Hashs to be deep_dup'able, chances are they also should go into Rails.
* It is not always obvious what a "deep" copy is.  For instance it is very hard to define one for a Proc instance.
* Recursive duplication may not be that simple to implement than you imagine.  For instance an Array can contain itself:
    r = [].tap {|r| r << r }
  How do you copy it deeply?
----------------------------------------
Feature #4514: #deep_clone and #deep_dup for Objects
https://bugs.ruby-lang.org/issues/4514

Author: Tom Wardrop
Status: Open
Priority: Normal
Assignee: 
Category: 
Target version: 


=begin
There's often a need to do a deep clone of an object, especially of Hash/Array trees. The typical work around to the lack of this functionality is to Marshall and then Unmarshall (e.g. Marshal::load(Marshal::dump(self)) ), which incurs more overhead than it probably should, and is not very semantic. My suggestion is to either provide #deep_clone and #deep_dup methods on the Object class, or to at least provide equivalent functionality for Hashes and Arrays, such as possibly a #deep_merge method for Hash. The exact implantation is not a large concern of mine; I'll let the experts determine the best method of achieving the desired outcome.
=end



-- 
http://bugs.ruby-lang.org/