From: Florian Gross <florgro@...>
Date: 2007-07-12T04:22:18+09:00
Subject: Re: to_str conversions and exceptions

On Jul 11, 7:35 pm, "John Lam (CLR)" <j...@microsoft.com> wrote:
> Silly question of the day:
>
> Does Ruby use respond_to? to test for the existence of a to_str method in methods like String#[int, int] = str? IOW does it do something like:

You will actually need to be careful though. You actually need to call
respond_to?() in Ruby. This means that overriding respond_to?() in
Ruby is possible. That is important because of objects like DRbObject
that delegate method calls across the network.

Here's a sample:

obj = Object.new

def obj.respond_to?(*a)
  p [:respond_to?, *a]
  return true
end

def obj.method_missing(*a)
  p [:method_missing, *a]
  return "hello"
end

str = "hi world"

str[0,2] = obj
# >> [:respond_to?, :to_str]
# >> [:method_missing, :to_str]

str # => "hello world"

And yup, this is missing from Rubinius specs.
Thank you for making me notice that. :)