[ruby-core:28556] Re: [Bug #2945] Regexp#=== is failed by an exception when the exception is occurred in method_missing

Hi,

On 2010/03/08, at 17:12, Yukihiro Matsumoto wrote:

> |> |Is this valid behavior?
> |> 
> |> I think so.  What makes you think it's invalid?
> |
> |I think the present behavior is unfortunate the following case.
> |I don't expect raising exception, but printing 2.
> 
> I have to repeat myself.  Why do you expect so?
> #method_missing raised an exception, no one captured.  Why do we
> expect exceptions to be captured implicitly?

Ok, I agree with you about that exceptions, no one captured,
shouldn't be captured implicitly.

But, I do still not understand Regexp#=== depends on method_missing.
I expect Regexp#=== with a non-string argument returns false.
In Regexp#===, if an argument doesn't have to_str method,
the argument is interpreted as a non-string, isn't it?
If so, Regexp#=== shouldn't raise an exception, but return false,
independently of the definition of method_missing.

> |  o1 = Object.new
> |  class << o1
> |    def method_missing(*args)
> |      raise "XXX"
> |    end
> |  end
> |  
> |  case o1
> |  when /aaa/
> |    puts 1
> |  when o
> |    puts 2
> |  end
> |  #=> `method_missing': XXX (RuntimeError)

--
Kenta Murata
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