support builtin for Kernel#clone

1 files changed, 29 insertions, 0 deletions

diff --git a/kernel.rb b/kernel.rb
new file mode 100644
index 0000000000..46d9438f85
--- /dev/null
+++ b/kernel.rb
@@ -0,0 +1,29 @@
+module Kernel
+  #
+  #  call-seq:
+  #     obj.clone(freeze: true) -> an_object
+  #
+  #  Produces a shallow copy of <i>obj</i>---the instance variables of
+  #  <i>obj</i> are copied, but not the objects they reference.
+  #  #clone copies the frozen (unless +:freeze+ keyword argument is
+  #  given with a false value) state of <i>obj</i>.  See
+  #  also the discussion under Object#dup.
+  #
+  #     class Klass
+  #        attr_accessor :str
+  #     end
+  #     s1 = Klass.new      #=> #<Klass:0x401b3a38>
+  #     s1.str = "Hello"    #=> "Hello"
+  #     s2 = s1.clone       #=> #<Klass:0x401b3998 @str="Hello">
+  #     s2.str[1,4] = "i"   #=> "i"
+  #     s1.inspect          #=> "#<Klass:0x401b3a38 @str=\"Hi\">"
+  #     s2.inspect          #=> "#<Klass:0x401b3998 @str=\"Hi\">"
+  #
+  #  This method may have class-specific behavior.  If so, that
+  #  behavior will be documented under the #+initialize_copy+ method of
+  #  the class.
+  #
+  def clone(freeze: true)
+    __builtin_rb_obj_clone2(freeze)
+  end
+end