From: Edwin Fine <efine145-nospam01 / usa.net>
Subject: Re: tk.rb warning in Turtle Graphics (#104)
Date: Sat, 2 Dec 2006 18:28:44 +0900
Message-ID: <86b6e853aac70b4d0b579cec71b1afd1 / ruby-forum.com>
> Well, I found a bizarre and (to me) totally inexplicable way to get rid 
> of the warning. This is from the quiz turtle_view.rb file. Adding an 
> explicit return value (any value; I used nil) to the draw method gets 
> rid of the warning. WTF???

Do you use the method "draw" at the end of callback operation?
If so, the method returns the result to the Tcl/Tk interpreter.
Then, the result (a Ruby's object) is converted to a string. 

Usually, an object of TkObject or its subclasses is converted to 
its @path value which is a string.
And when pass the string to Tcl/Tk side, @encoding check is required.

nil or a numeric doesn't need @encoding check.
-- 
Hidetoshi NAGAI (nagai / ai.kyutech.ac.jp)