From: Shri Borde <Shri.Borde@...>
Date: 2009-02-06T02:56:17+09:00
Subject: [ruby-core:21861] Re: Regexp interpolation does not give equality

Yes, I realized this later. Substitution always uses to_s, and to_s of a Regexp uses the (?-mix:<expr>) form.

And equality of Regexps just looks at the regexp string, and does not try to do anything more fancy.

-----Original Message-----
From: Ondrej Bilka [mailto:neleai@seznam.cz] 
Sent: Wednesday, February 04, 2009 11:21 PM
To: ruby-core@ruby-lang.org
Subject: [ruby-core:21851] Re: Regexp interpolation does not give equality

On Thu, Feb 05, 2009 at 12:32:11AM +0100, Shri Borde wrote:
> Any idea why the second expression results in false? Its seems like both the regexpes are similar (to_s gives the same result), but the == method just fails to realize that they are really identical.
irb(main):001:0> a="a"
=> "a"
irb(main):002:0> b=/#{a}/
=> /a/
irb(main):003:0> c=/#{b}/
=> /(?-mix:a)/
> 
> irb(main):001:0> re = /Hello/
> => /Hello/
> irb(main):002:0>  /#{re}/ == /Hello/
> => false
> irb(main):002:0> /#{re}/.to_s == /Hello/.to_s
> => true
> irb(main):003:0> str = "Hello"
> => "Hello"
> irb(main):004:0> /#{str}/ == /Hello/
> => true
> 
> Thanks,
> Shri
> 

-- 

transient bus protocol violation