From: Florian Frank <flori@...>
Date: 2002-12-18T02:43:56+09:00
Subject: Re: Deep copy in Rub?

On 2002-12-18 01:53:47 +0900, Jim Freeze wrote:
> > My Ruby has it now:
> > 
> > [flori@lambda flori](0)$ irb --prompt xmp
> > VERSION
> >     ==>"1.7.3"
> > o = ["foo"]
> >     ==>["foo"]
> > oc = o.deep_clone
> >     ==>["foo"]
> > o[0].equal? oc[0]
> >     ==>false
>  I just did a CVS get this morning...

OK. The only problem is that I can't commit my patches there. ;)

[flori@lambda ruby](0)$ cvs diff object.c 
Index: object.c
===================================================================
RCS file: /src/ruby/object.c,v
retrieving revision 1.96
diff -p -u -r1.96 object.c
--- object.c    10 Dec 2002 06:23:40 -0000      1.96
+++ object.c    17 Dec 2002 17:34:51 -0000
@@ -152,6 +152,21 @@ rb_obj_clone(obj)
 }
 
 VALUE
+rb_obj_deep_clone(obj)
+    VALUE obj;
+{
+    VALUE clone;
+
+    if (rb_special_const_p(obj)) {
+        rb_raise(rb_eTypeError, "can't clone %s",
rb_class2name(CLASS_OF(obj)));
+    }
+    clone = rb_marshal_load(rb_marshal_dump(obj, Qnil));
+    RBASIC(clone)->flags = RBASIC(obj)->flags | FL_TEST(clone,
FL_TAINT);
+    return clone;
+}
+
+
+VALUE
 rb_obj_dup(obj)
     VALUE obj;
 {
@@ -1332,6 +1347,7 @@ Init_Object()
     rb_define_method(rb_mKernel, "class", rb_obj_class, 0);
 
     rb_define_method(rb_mKernel, "clone", rb_obj_clone, 0);
+    rb_define_method(rb_mKernel, "deep_clone", rb_obj_deep_clone, 0);
     rb_define_method(rb_mKernel, "dup", rb_obj_dup, 0);
     rb_define_method(rb_mKernel, "copy_object", rb_obj_copy_object, 1);

The only problem is that marshal doesn't copy the frozen flags for the
clone. If it would it could be possible to have "deep_clone" and
"deep_dup".

-- 
Most people would rather die than think; in fact, they do so.
  -- Bertand Russell