What's going on here? (weird Ruby 1.9 incompatibility)

ruby-talk
1

class A
  def a
    'yay'
  end
end

class B
  def initialize(&meth)
    class << self; self; end.__send__(:define_method, :b, &meth)
  end
end

b = B.new &A.new.method(:a)
p b.b

Ruby 1.8 prints:
"yay"

Ruby 1.9 complains (on the p b.b line):
14:in `<main>': wrong number of arguments (1 for 0) (ArgumentError)

···

--
Tony Arcieri
medioh.com

2

I tried changing A to have the following definition:

class A
  def a(*args)
    args
  end
end

Now:

Ruby 1.8:

or if you call b.b(1,2,3):
[1,2,3]

Ruby 1.9:
[nil]

or if you call b.b(1,2,3):
[1]

Is this a bug?

···

On Sat, Mar 29, 2008 at 12:08 PM, Tony Arcieri <tony@medioh.com> wrote:

Ruby 1.8 prints:
"yay"

Ruby 1.9 complains (on the p b.b line):
14:in `<main>': wrong number of arguments (1 for 0) (ArgumentError)

--
Tony Arcieri
medioh.com

3

I added the output of the arity of the methods, looks very much like a
bug to me, are you familiar with the Bug Reporting process?

<code>
ma = A.new.method(:a)
p ma.arity # --> 0
b = B.new( &ma )
mb = b.method(:b)
p mb.arity # --> 0

p b.b # bombs
</code>

Cheers
Robert

···

On Sat, Mar 29, 2008 at 7:08 PM, Tony Arcieri <tony@medioh.com> wrote:

class A
  def a
    'yay'
  end
end

class B
  def initialize(&meth)
    class << self; self; end.__send__(:define_method, :b, &meth)
  end
end

b = B.new &A.new.method(:a)
p b.b

Ruby 1.8 prints:
"yay"

Ruby 1.9 complains (on the p b.b line):
14:in `<main>': wrong number of arguments (1 for 0) (ArgumentError)

--
Tony Arcieri
medioh.com

--
http://ruby-smalltalk.blogspot.com/

---
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Ludwig Wittgenstein