Performance is one of those nasty things that can go from being a non- issue to THE issue (next to correctness) in the blink of an eye. I am curious, however. How much total performance difference did this change make? I'm betting <1%.
Nathan David Chelimsky wrote: > On Thu, Nov 27, 2008 at 8:17 PM, Mark Wilden <[EMAIL PROTECTED]> wrote: >> On Thu, Nov 27, 2008 at 5:57 PM, Brian Takita <[EMAIL PROTECTED]> >> wrote: >>> I'm wondering if this is a discussion about taste. >> I think you're right. I've been using the 'def self.foo' style in various >> languages for almost 20 years, so of course it feels more natural to me. >> These languages (except for Smalltalk) had nowhere near the metaprogramming >> capability nor 'objects all the way down'-ness of Ruby, and 'class << self' >> is one of those things. >> >> ///ark > > FWIW, the blog that led to this discussion suggested a performance > impact as well. As RSpec has gotten dinged for being slower than > alternatives, that interested me, so I did a little experiment def'ing > methods 10k times with def self.method and class << self; def method > .... > > def self.method ran an average of 10% faster. > > Based on just that, I've all but eliminated class << self from rspec in git. > > Crazy? On Nov 25, 8:52 am, "David Chelimsky" <[EMAIL PROTECTED]> wrote: > On Tue, Nov 25, 2008 at 8:39 AM, Zach Dennis <[EMAIL PROTECTED]> wrote: > > On Tue, Nov 25, 2008 at 9:38 AM, Zach Dennis <[EMAIL PROTECTED]> wrote: > >> On Tue, Nov 25, 2008 at 8:41 AM, Matt Wynne <[EMAIL PROTECTED]> wrote: > >>> Sorry, I know this is off-topic, but I'd really like to know what the > >>> revered ruby-hackers who read this list think. > > >>> See > >>>http://ozmm.org/posts/class__self_is_harmful.html > > >>> I have adopted class << self, partly from reading RSpec and Cucumber's > >>> code > >>> as I learn Ruby. I personally think of class methods (or 'static' methods) > >>> as being in a kind of 'holding pen' waiting to be factored off onto a > >>> proper > >>> class of their own, so I rather like the clear way you can group them in a > >>> 'nameless' metaclass ready for the exit door. > > >>> I also really like the clarity of seeing the invisible metaclass for what > >>> it > >>> is. > > >>> What do people think? How can this be harmful? > > > I forgot to add it is considered harmful because it can so easily be > > abused and make readability of the code very difficult to understand. > > Especially when doing meta-meta programming. :) > > >> I think the issue is that people are using class << self to access the > >> virtual class when they don't need it. I've seen code where you have > >> to scroll to see all of the methods implemented inside of class << > >> self. Adding methods to a virtual class does make method dispatching > >> in ruby less efficient, but I don't think enough to render it > >> non-usable. > > >> The virtual class of an object (class or instance alike) gives you the > >> ability to modify the object in ways that a simple class method > >> usually does not allow. For example, if you want to break down a class > >> method into a couple of methods, but you don't want to support all of > >> the methods as a public API. Here you can use class << self to > >> privately scope some of those helper methods that you just decomposed. > > >> My rule of thumb is to use it when I can't easily achieve the same > >> result using other mechanisms, but not to use it just cause'. > > One thing Chris points out in his blog is that 'def self.method_name' > is perfectly fine, and that it makes refactoring easier. My experience > is different, because I'm often searching for methods with 'dev > method_name' - this is actually one of the reasons I have preferred > 'class << self'. > > That said, I'm all for speeding things up where we can, so I'll be > looking into this in rspec. I just found 22 uses of 'class << self' in > rspec. Sometime soon I'll see how many of them I feel I can get rid > of. > > Cheers, > David > > > > > > >> -- > >> Zach Dennis > >>http://www.continuousthinking.com > >>http://www.mutuallyhuman.com > > > -- > > Zach Dennis > >http://www.continuousthinking.com > >http://www.mutuallyhuman.com > > _______________________________________________ > > rspec-users mailing list > > [EMAIL PROTECTED] > >http://rubyforge.org/mailman/listinfo/rspec-users > > _______________________________________________ > rspec-users mailing list > [EMAIL PROTECTED]://rubyforge.org/mailman/listinfo/rspec-users _______________________________________________ rspec-users mailing list rspec-users@rubyforge.org http://rubyforge.org/mailman/listinfo/rspec-users
