[doc patch->object.c] instance_variable_set will create an instance var

This wasn't clear from the docs, or the example, but I tried it:

$ irb < ivarset.rb 
>> class Fred
>>   def initialize(p1, p2)
>>     @a, @b = p1, p2
>>   end
>> end
=> nil
>> fred = Fred.new('cat', 99)
=> #<Fred:0x2fd764 @a="cat", @b=99>
>> fred.instance_variable_set(:@a, 'dog')
=> "dog"
>> fred.instance_variable_set(:@c, 'cat')
=> "cat"
>> fred.inspect
=> "#<Fred:0x2fd764 @a=\"dog\", @b=99, @c=\"cat\">"
>> 

Doc patch:


Index: object.c
===================================================================
RCS file: /src/ruby/object.c,v
retrieving revision 1.134.2.23
diff -u -r1.134.2.23 object.c
--- object.c    11 Jan 2005 15:36:52 -0000      1.134.2.23
+++ object.c    6 Feb 2005 22:14:26 -0000
@@ -2009,7 +2009,8 @@
  *  
  *  Sets the instance variable names by <i>symbol</i> to
  *  <i>object</i>, thereby frustrating the efforts of the class's
- *  author to attempt to provide proper encapsulation.
+ *  author to attempt to provide proper encapsulation. The variable
+ *  did not have to exist prior to this call.
  *     
  *     class Fred
  *       def initialize(p1, p2)
@@ -2018,7 +2019,8 @@
  *     end
  *     fred = Fred.new('cat', 99)
  *     fred.instance_variable_set(:@a, 'dog')   #=> "dog"
- *     fred.inspect                             #=> "#<Fred:0x401b3da8 
@a=\"dog\", @b=99>"
+ *     fred.instance_variable_set(:@c, 'cat')   #=> "cat"
+ *     fred.inspect                             #=> "#<Fred:0x401b3da8 
@a=\"dog\", @b=99, @c=\"cat\">"
  */
 
 static VALUE



Thanks,
Sam