From: Robert Klemme <shortcutter@...>
Date: 2012-10-15T16:15:15+09:00
Subject: Re: About define_method

On Mon, Oct 15, 2012 at 8:37 AM, li shoubo <lists@ruby-forum.com> wrote:

> please help me to figure out why I can not use the first solution.

You simply cannot define methods which use block passed to them via
define_method as you have found out.  Minimalistic example:

$ ruby -e 'module Kernel;def foo; yield 1 end end; foo {|x| p x}'
1
$ ruby -e 'module Kernel;define_method(foo) { yield 1 };end;foo {|x| p x}'
-e:1:in `<module:Kernel>': undefined local variable or method `foo'
for Kernel:Module (NameError)
        from -e:1:in `<main>'

Another variant is to use class_eval:

$ ruby -e 'Kernel.class_eval "def foo; yield 1 end";foo {|x| p x}'
1

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/