2 files changed, 32 insertions, 1 deletions
diff --git a/mrbgems/mruby-object-ext/mrblib/object.rb b/mrbgems/mruby-object-ext/mrblib/object.rb
index 581156cb0..f014df469 100644
--- a/mrbgems/mruby-object-ext/mrblib/object.rb
+++ b/mrbgems/mruby-object-ext/mrblib/object.rb
@@ -1,4 +1,18 @@
-class Object
+module Kernel
+  # call-seq:
+  #   obj.yield_self {|_obj|...} -> an_object
+  #   obj.then {|_obj|...}       -> an_object
+  #
+  # Yields <i>obj</i> and returns the result.
+  #
+  #   'my string'.yield_self {|s|s.upcase} #=> "MY STRING"
+  #
+  def yield_self(&block)
+    return to_enum :yield_self unless block
+    block.call(self)
+  end
+  alias then yield_self
+
   ##
   #  call-seq:
   #     obj.tap{|x|...}    -> obj
diff --git a/mrbgems/mruby-object-ext/src/object.c b/mrbgems/mruby-object-ext/src/object.c
index ac26cdc94..d3e7a9c50 100644
--- a/mrbgems/mruby-object-ext/src/object.c
+++ b/mrbgems/mruby-object-ext/src/object.c
@@ -46,6 +46,22 @@ nil_to_i(mrb_state *mrb, mrb_value obj)
 
 /*
  *  call-seq:
+ *     obj.itself -> an_object
+ *
+ *  Returns <i>obj</i>.
+ *
+ *      string = 'my string' #=> "my string"
+ *      string.itself.object_id == string.object_id #=> true
+ *
+ */
+static mrb_value
+mrb_f_itself(mrb_state *mrb, mrb_value self)
+{
+  return self;
+}
+
+/*
+ *  call-seq:
  *     obj.instance_exec(arg...) {|var...| block }                       -> obj
  *
  *  Executes the given block within the context of the receiver
@@ -102,6 +118,7 @@ mrb_mruby_object_ext_gem_init(mrb_state* mrb)
   mrb_define_method(mrb, n, "to_f", nil_to_f,       MRB_ARGS_NONE());
 #endif
   mrb_define_method(mrb, n, "to_i", nil_to_i,       MRB_ARGS_NONE());
+  mrb_define_module_function(mrb, mrb->kernel_module, "itself", mrb_f_itself, MRB_ARGS_NONE());
 
   mrb_define_method(mrb, mrb_class_get(mrb, "BasicObject"), "instance_exec", mrb_obj_instance_exec, MRB_ARGS_ANY() | MRB_ARGS_BLOCK());
 }