The Only Time You Should Use Polymorphism
ฝัง
- เผยแพร่เมื่อ 16 พ.ค. 2024
- The only time you should use subtype polymorphism is when you have behavioural variation in the subtypes. I teach two university courses on object oriented programming and I see this problem a lot. Let me explain. RECOMMENDED READING:
🛠️ geni.us/k8KhT3 (Refactoring)
⭐️ geni.us/zzlx (Dependency Injection: Principles, Practices, and Patterns)
💎 geni.us/hNDE (Elegant Objects)
🏛️ geni.us/IBhtLnh (Clean Architecture)
🧩 geni.us/nlbA6 (Head First: Design Patterns)
Read my FREE book on Object Oriented Programming:
🚀 theobjectorientedway.com
Watch next:
• Always Use Interfaces
CONTENTS:
00:00 Thesis
01:16 Example 1
03:28 Example 2
06:25 Example 3
13:26 Summary
![[TH] 2024 PMSL SEA W2D1 | Summer | ถ้าไม่พร้อมลุย ได้ไปคุยกับรากมะม่วง](http://i.ytimg.com/vi/XlkKtVvBxac/mqdefault.jpg)
He randomly came back after three years! Tak! Good to see you again.
Yessssss I'm glad he is back man, I've learned so many things important on my career because of his videos
Love him, jest super
OMG I can't believe this, I asked him last week on Twitter when he is coming back..and here he is. 🐐
What are the chances he’ll stay with us for some time now 😅
@@DerRabeKirilldepends if project manager leaves him alone
Finally he remembered his password
🤣🤣
called it!! 😂
Where you were?, will you make video contunue now@@ChristopherOkhravi
This must have been some variation in data.
I like to think, that you got so annoyed by someone at work using subtype polymorphism the wrong way, that it brought you back here ;)
I teach at a university so I read a lot of student code 😉
in which university do you teach I need to attend there, you're a CS legend
@@ChristopherOkhravi
I wish more people in your team do things in wrong way that you make more videos to teach others 😂
Man, your notification popping up is the best thing happened in months❤, please don't disappear again :)
literally just watched your design patten playlist, thinking why hasn't he posted for 3 years. perfect timing
Welcome back! Got a huge amount of value out of this channel in my early days of becoming a dev
Have been watching your Design Patterns series and the code walks videos and was always thinking if I ever wanted to have a youtube channel it would have been of this style. If only he was back. Wish granted, welcome back, so happy to see notifications from you! :DDDD
Suddenly you appeared out of thin air, please be consistent. Love your content.
No one told you to wait
we aint entitled to his time
He can post whenever he feels like posting. How entitled are you. Anyway thanks for the content ignore comment like above
I've never been more engaged with software engineering TH-cam content. Your presentation skills are excellent.
I didnt even fully read the title, I just saw the thumbnail and clicked. Welcome back good sir.
Great to see you again Christopher. Miss your videos of design patterns and discussions about principles. Welcome Back!!
Best notification from TH-cam in ages. I hope you've got more for us. 100% my favourite videos covering software development!
I came to the comments section to share my excitement about your return.
But, wow, I didn't expect there to be so many of us!
please continue have been rewatching your old stuff so glad to see this
Last month i was discussing with my friend about Design patterns and in that discussion i recommended him your channel. While discussing i said to him that don't know why you aren't posting any content. I was little bit worried about you. Now i am very glad to see you back. 🥳🥳🎉🎉❤❤❤
Welcome baaaaack!!!!!!!!! Happy to see you around after so much time! Hope you'll stay for a while, your content and way of explaining things are precious.
Awesome to see you back Chris! I’ve learned a lot from your videos, and have always enjoyed hearing your perspective on things. 😎👍
I've been watching your playlists whilst working on my project over the last year, and this video is so relevant to what I'm currently working on, and exactly what I've been asking myself while working on my current systems. Being self taught I don't know the theory very well, so I would had never known that I was dealing with 'sub-type polymorphism'. Good to know I've been going down the right path, and also to know what it's called!
Love to see you again, I look forward to rewatching as much of your videos as possible !
I started watching him on thursday, fell in love in his way of teaching, and was thrilled when saw that last video was posted 3 years ago. And now he appears out of nowhere 😂 If you were giving lectures on my Uni, i wouldnt miss a single one
The man, the legend, welcome back
From last week I started watching your Design Pattern playlist and thinking why Chris stopped posting videos for last 3 years. To my surprise there was a notification😮. Your teaching is so great and natural, not everyone gets so easily. Keep up the Great work!
happy to see you are back! keep the content coming! learning a lot.|
love the whiteboard, the editing and the why you teach :)
Happy to see you upload after 3 years love the way you teach..
Your teaching is the greatest and simpler....❤
Glad to see you're back uploading videos! Your series on design patterns were instrumental in taking another step in my career!
WHOA! i started watching your pattern videos like a week ago, binging them while at the gym, while taking walks, etc. i was like "eh it's been a long time since hes posted...he was a good teacher" and then here you are!!
I did not expect you coming back, loved your design patterns, glad to see you're doing well!
Whoa, seeing you in my sub box is not something i expected today. Long time viewer of the channel, since the ramda days! Good to see you back.
Your channel helped me get into functional programming, and now i'm absolutely obsessed. Do you have any plans for more FP related videos?
Welcome back Christopher. Good to see you back 😊 Keep up the good work and make learning fun and easy. All power and good wishes ❤
Glad TH-cam was smart enough to recommend your video. Glad to see you posting. Always top notch stuff.
Hey @Chris, it's great to see you after such a long time! I've always been a fan of the way you present content with crisp editing.
I watch your videos and you are the first teacher whoes course i can buy without thinking about money.
Man, I was so happy to see your face in my feed again. Glad to have you back, your videos always helped me understand these concepts so much better.
I missed your videos, thanks for coming back!
Your Design pattern playlist is the best I have ever seen on any channel/courses. It was about a year ago I started and completed the DP videos, but was disappointed to see no more , and randomly today this video pops up on my feed, very happy to see you again hopefully you will complete the rest of the patterns too 😊. I tried connecting you on LinkedIn too but it was restricted I think 😅.
Welcome back Chris. Have learnt a lot from your design pattern series!
Oh my god. I used to watch your videos when I started learning programming in 2021. Right now, I have an interview with Google scheduled next week. You don't know how happy I am to see you back. Thanks for coming and welcome back :)
Glad to hear 😊 Best of luck on your interview!
Welcome back, I have missed your content, it is great. Your analysis has been vital to my programming evolution, if only I'd have had teachers with your energy.
Finally you are back!
I enjoyed so much your design patterns playlist.
I've really missed these talks. Welcome back!
Legend is backkk!!! Good to see you, your system design videos are epic!! MASSIVE THANKS
So happy to see you back. You're the sole educator whose TH-cam videos I choose to view at regular speed, even when they extend to an hour.
Welcome back! Your videos helped me a ton while getting my degree - good to see you're still at it!
I missed your tutorials man, good to have you back!
it's been a very long time, nice to see again man!!
I don't have words to describe how happy I am to see you back.. Love your style of teaching
I didn't learn anything, but the way you described the information in the video *clarified* what I'd already known -if that makes sense.
You are excellent at explaining things in very clear terms, and I appreciate that. Subbed.
I'm very happy to hear that. Also, thank you for the sub. Welcome 😊
Thanks for your work, I got a masters in software engineering 2 years ago and your videos on the design patterns really helped me.
Kul att se att du är tillbaka igen! Dina förklaringar av designmönster hjälpte mig enormt under skoltiden. 👍
Man önskade att fler lärare var såhär pedagogiska.
Tack så mycket!
Welcome back! Please upload more videos on system design and LLD. We appreciate your effort!
I like this format. My ADD was trying its best to block the info, but this guy just kept going :)
Oh hey look who's back! Thanks for the video! Ur gof patterns videos helped me a ton a few years back
Glad that see you again, hope I can see another series also before I die. But high quality takes times, I'm really enjoying when watching your videos.
Welcome back! So excited to see you back! huge fan of your videos. Thank you!
No way!!! You are back! Glad to see!
Thanks for all of these and welcome back!
omg great to see u again! Ur videos has helped me tremendously during my time at chalmers, and im actually now TEACHING the same course i used ur videos to pass years before! Will recommend ur channel to all my students!
Thank you 🙏😊 And congratulations
It's so good to have you back. Thank you 😊
you did really well with this video, i was able to flip into it and out of it, while just listening and you never lost me. i now know what you put into this video and thats always nice!
Welcome Back, Great to see you after 3 years :D
Welcome back ! , good decision to come back , your content is wonderful
This is the first video I watch from you. It makes complete sense, no idea why I never though of it like this. Looking forward to more videos!!
I'm very happy to hear. Welcome 😊
Wow man, so glad to see u again, you are an amazing teacher, please keep the quality content😊
I didn't realise you hadn't posted for three years! I've been taking a break from coding but had to watch this video! Please keep posting!
Good to see you after 3 years. I love the way you teach.
Welcome back! Good to watch your video again!
Damn you're back! Thank you very much for the content!
Loved this video. Thank you so much for the bite-size CS training. Love your style, heart, and expertise.
Thanks for sharing your valuable knowledge again. Your videos about design patterns helped me a lot when I landed my first job as a software developer. I hope 🤞 you don’t give a break anymore 😊
Love to see you back, hope all good at your end. You have unique way of communicating complex things, Keep making video.
Thank you bro for coming back
Welcome back and thanks for awesome videos ❤
Welcome back, sir. Happy to know you are still creating content.
Previously, thank you for the knowledge, and welcome back.
What I get from the explanation is:
We should/must prefer to be implicit about a specific type of data that has the same structure and behavior, instead of being explicit (where we define it based on the actual concept or domain) about that type (CMIW).
Glad to see you again, really like your teaching style
We've been waiting for you to come back! - so WELCOME BACK ^^!
I just remebered your design patterns series from years ago and was looking what you were up to. Great timing.
😊😊
Thanks for checking in again 😊
Welcome back! Good to see you!
Thanks for coming back man
I was waiting for this quality content again, thank you so much !!!!
The king of Design patterns is back🔥
Welcome back Chris. loved this one.🙏
Great video thank you, and welcome back sensei
Word to mother....ur design patterns videos helped me nail an interview in 2017 🤣🤣🤣. Now I'm a Lead software engineer. Thanks
I would add a point that "variations in behavior" can also come from _outside_ the class - a class can just be a data type, without being responsible for all the ways the data will be used. Imagine an Attack subtype, EnergyAttack, which has an additional property EnergyType. Now Scratch is a base Attack instance, and Thunderbolt is an EnergyAttack (with EnergyType = Lightning). Looking at just the class definitions, you could say this is a data-only variation, but it makes sense because the change is in the data structure (an additional property), not just values. These subclasses may or may not implement variations in behavior themselves, but _allow for_ external variations by being different types: We may have many general functions that work with the Attack type, as well as some functions that accept EnergyAttack specifically and work with the EnergyType property.
Thank you again for your time creating this great content ❤
Great to see you again! Love your content, the way you explain complicated things is simple and approachable, love the mustaches also 🙂
Hej, you are back. I have mist your videos, they have helped me so very much. Thank you for another interesting and great video.
Excellently summarized and put into perspectives. 👌🏻
I'm extremely happy you are back. Thank you.
Your teaching is simpler and also in depth, good to see you back on youtube. Please create more good quality content !!
Love your videos! Great to see them again!
Welcome back! Thank you for this! The cliffhanger in the end...oh man, please don't let us hanging for too long
Gotta leave some loops open 😊😊
He's alive!!! Glad to have you back!
Good to see you again! Welcome back!
Awesome points on polymorphism. Never thought that. Thanks. Really helpful.
You're a fantastic teacher. Welcome back !!!
bro scared me with that jump in the frame haha welcome back! Thanks for the Design Patterns series which helped me a lot!
Finally you are back I missed your lectures, thank you sooooooooooooo much ...