This was an amazing explanation. I was super impressed that you had decided to start with the actual C representation of Objects and Classes. Everytime I need to brush up on the Ruby Objected Model (and I have had to, every 3 months :)), starting with the C representation feels like the best way to get a handle on it. Thanks!
Cool video, very well presented. I'd like to share some interesting implications that I found out: 1. Class methods are instance methods of a class' singleton class. You can prove that by calling "instance_methods" on a singleton class. So the deeper thruth is that every method is an instance method. A method can also be a singleton method, it only depends on the context (context in that case is "it is defined on the singleton class"). 2. There is no distinction between include and extend, other than "context related". extend is a disguised include, and it happens on an instance's singleton class. extend makes methods callable directly on one instance (be it a class instance, a regular instance, or whatever), whereas include makes methods callable on instances generated by a certain class. 3. Modules are containers of constants and methods, but are also used for namespacing (isolation). Classes are referenced by constants (and so are modules), so you can perfectly define classes inside modules. Class instances are descendants of Module, so they can also be used for namespacing (just like modules). That means you can also define modules inside classes. When you include a module inside a class, the module's methods will work on instances generated by that class. Also, if there is any class defined inside the module, you will be able to reference that class directly, without prepending the namespace.
This explanation is the first time I have ever started to understand the actual reality of an object. It seems like it's just a reference to functions! It looks like you haven't posted things recently, I hope all is well. If you do get the urge to make more videos, I think the world could really use your style of explanation for how Rails works. I know it isn't magic because it's just a computer doing what it's told, but without anyone telling us what it's actually doing it sure looks like magic!! Thanks again for this video it was really helpful.
Thanks, you're very kind! :) I probably need to rewatch it myself actually as I pretty much don't need to keep any of this in my head anymore for the sort of work I'm doing.
Really really great presentation!! IMHO there is one thing you could add to it, which is: what happens when we include several modules (with some simple example showing reverse inheritanceinclusion order): class A include Z include Y end A.ancestors => [A, Y, Z, Object, Kernel, BasicObject] Anyway, superb and clear explanation of Ruby Object Model.
When you say "only classes have methods" how are singleton methods implemented? Still via a lonk to the class but with a ref to the specific object on which the singleton method exists...?
It's an old video from a training course I used to do, so unfortunately not, I don't have the time right now. BUT.. the good news is Ruby Under A Microscope is a book that pretty much covers all of this stuff and more, so it's worth getting a hold of that. The author's blog (Pat Shaughnessy) also has some excellent blog posts which cover similar ground.
This is wonderful. I can learn about Ruby and the british accent at the same time :)
This was an amazing explanation. I was super impressed that you had decided to start with the actual C representation of Objects and Classes. Everytime I need to brush up on the Ruby Objected Model (and I have had to, every 3 months :)), starting with the C representation feels like the best way to get a handle on it. Thanks!
on 2022, this video is still relevant,, and still awesome, ! 34 minutes of pure GOLD!!!, thanks a lot!!!
Cool video, very well presented. I'd like to share some interesting implications that I found out:
1. Class methods are instance methods of a class' singleton class. You can prove that by calling "instance_methods" on a singleton class. So the deeper thruth is that every method is an instance method. A method can also be a singleton method, it only depends on the context (context in that case is "it is defined on the singleton class").
2. There is no distinction between include and extend, other than "context related". extend is a disguised include, and it happens on an instance's singleton class. extend makes methods callable directly on one instance (be it a class instance, a regular instance, or whatever), whereas include makes methods callable on instances generated by a certain class.
3. Modules are containers of constants and methods, but are also used for namespacing (isolation). Classes are referenced by constants (and so are modules), so you can perfectly define classes inside modules. Class instances are descendants of Module, so they can also be used for namespacing (just like modules). That means you can also define modules inside classes. When you include a module inside a class, the module's methods will work on instances generated by that class. Also, if there is any class defined inside the module, you will be able to reference that class directly, without prepending the namespace.
You turned a very complex subject into something simple. And simples is > genius. Your sir, are more than a genius. Best explanation ever. Caviar.
OUTSTANDING!
Brilliantly presented in a clear manner.
Thank you Peter.
Thanks for watching!
Great Video man you have just cleared the core OOP concepts that are used in Ruby on Rails. Thank you so much
This is one of the most fantastic and in depth videos. Thank you for your effort.
Sir, you are THE BEST. Period. Thank you!
This explanation is the first time I have ever started to understand the actual reality of an object. It seems like it's just a reference to functions! It looks like you haven't posted things recently, I hope all is well. If you do get the urge to make more videos, I think the world could really use your style of explanation for how Rails works. I know it isn't magic because it's just a computer doing what it's told, but without anyone telling us what it's actually doing it sure looks like magic!!
Thanks again for this video it was really helpful.
Thanks, you're very kind! :) I probably need to rewatch it myself actually as I pretty much don't need to keep any of this in my head anymore for the sort of work I'm doing.
Dude... this is the first time I *really* understand eigenclasses. Thank you!
Fantastic video - you've made several concepts that was fuzzy on absolutely clear. Great work!
Really really great presentation!!
IMHO there is one thing you could add to it, which is: what happens when we include several modules (with some simple example showing reverse inheritanceinclusion order):
class A
include Z
include Y
end
A.ancestors
=> [A, Y, Z, Object, Kernel, BasicObject]
Anyway, superb and clear explanation of Ruby Object Model.
This is the BEST video on the topic I could find. THANK YOU!!! :)!
Thank you very much Mr Cooper.
This is great explanation. Ruby OOPs feels much easy after this video. Thank you Peter. :)
That red at 17:50 almost burned my eyes :D
Great explanation!
Great explanation. I have a much firmer understanding of the Object Model now! This will help me when I'm debugging, for sure.
Excellent is the only word that can describe this content.
Thanks for sharing this video! You've made some difficult concepts crystal clear. I now "get it".
Amazing explanation. Thank you
Like to see the script kiddies understand this... Kind of makes me appreciate my distant background in C and C++.
You are a fantastic teacher! Thanks for everything.
Nice, feels like it never gets obselete
Is it possible to include a module within a module?
Your videos are excellent and engaging!
This is the real shit, old boy. Capital !
When you say "only classes have methods" how are singleton methods implemented? Still via a lonk to the class but with a ref to the specific object on which the singleton method exists...?
Had I only waited 30s. Answered at ~16min. Great video, thanks!
Thank you very much sir!
YOU ARE A GENIOUS
hi! can you publish text version of this cast?
It's an old video from a training course I used to do, so unfortunately not, I don't have the time right now. BUT.. the good news is Ruby Under A Microscope is a book that pretty much covers all of this stuff and more, so it's worth getting a hold of that. The author's blog (Pat Shaughnessy) also has some excellent blog posts which cover similar ground.
Peter Cooper thank you) i've been reading it)
Genius :)