From: Rick DeNatale <rick.denatale@...>
Date: 2009-08-27T04:46:34+09:00
Subject: Re: ||= with 1.8 and 1.9 ?

On Wed, Aug 26, 2009 at 2:49 PM, Aldric Giacomoni<aldric@trevoke.net> wrote:
> Joel VanderWerf wrote:

> Well, then... It -IS- assigning something, isn't it, since there's no
> value to @test ? Why does it return something other than the result of
> the assignment?

Right, the question is why in Ruby 1.9 is using the 'not a test'
returned from the setter method in the case of ||= unlike Ruby 1.8.x
and like itself in the = case:

To make it a bit clearer by moving the assignments out of the p calls:

puts RUBY_VERSION

class OrOrEquals
  def test
    @test
  end

  def test=(test)
    @test = test
    'not test'
  end
end

o = OrOrEquals.new

direct = o.test = 'a test'
p direct
o.test = nil
with_oror = o.test ||= 'a test'
p with_oror
p o.test
o.test = nil

$ multiruby or_or_equals.rb
/opt/local/lib/ruby/site_ruby/1.8/rubygems/source_index.rb:144:
warning: /Users/rick/.gem/ruby/1.8/specifications: Permission denied

VERSION = 1.8.6-p368
CMD     = ~/.multiruby/install/1.8.6-p368/bin/ruby or_or_equals.rb

1.8.6
"a test"
"a test"
"a test"

RESULT = 0

VERSION = 1.8.7-p160
CMD     = ~/.multiruby/install/1.8.7-p160/bin/ruby or_or_equals.rb

1.8.7
"a test"
"a test"
"a test"

RESULT = 0

VERSION = 1.9.1-p0
CMD     = ~/.multiruby/install/1.9.1-p0/bin/ruby or_or_equals.rb

1.9.1
"a test"
"not test"
"a test"

I've raised this on ruby-core.  I'm interested to see what Matz & co
have to say.


-- 
Rick DeNatale

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