Metaclasses in Python
149,972
2021-10-02に共有
We go over what metaclasses are and give some notable examples, including: abstract base classes, adding function overloads, and dataclasses or code generation.
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Python metaclass docs: docs.python.org/3/reference/datamodel.html#metacla…
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CHAPTERS
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0:00 Intro
1:28 What is a metaclass
3:58 Simplest possible metaclass
4:59 Load time metaclass
6:08 Abstract base classes
8:03 Function overloads
14:10 Dataclass code generation
15:01 Giveaway instruction
コメント (21)
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i will literally never have a practical use case for this but it still makes me happy it exists edit: ok within a year I have used it several times I retract my previous statement
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This video was so magical I'm tempted to call it a __video__
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Metaclasses looks very powerfull, unfortunately most people using "powerfull" features in a big codebase usually leaves the most powerfull mess to be maintained. Great video! #pycharm
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My mind is blown. So many possibilities once you know what Python does under the hood. I would find it super interesting to learn more about how C-bindings like numpy uses them are built and how one could add them too. #pycharm
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Since I've lot's of work nothing to do right now, I counted how often you've said the word 'class' and 'metaclass' in this video: · class ⟶ 62 times · metaclass ⟶ 33 times Oh my god, I watched the video on 2x speed and at 1:37, my brain just started to hurt. I really like your content by the way. There are so many useful python features I've hever heard of before. 👍
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Man the information density in your videos is mindboggling. Every 20 seconds there's something I'd need to sit an hour for to fully absorb the concept and the code. Well done, thanks
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I feel like your videos have given me a really deep understanding and appreciation of all the internal magic that goes on behind the scenes on Python. Thanks for the content!
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one of my favorite things about python is how modular the language itself is. You can just overload anything you want, and having the syntax be so malleable is so fun!!
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I taught Python for 2 years at the university level. I thought I knew more deep wizardry than any person should know. After seeing this, it's clear that I know nothing. #pycharm
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"the type of big A is a type but the type of small a is big A, whereby the type of type is type" That's exactly the feature you will probably not use for a long time, but years from now you will remember and it will save your life! Best thing about python, it's not like other languages where many base features are hard-coded, but you can customize EVERYTHING #pycharm
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This is a terrible idea, super slow, and very very dangerous. I absolutely love it.
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This is actually that rare gem content found under the depths of the internet. Been trying to wrap around meta-classes for a week now, with so little luck. The docs/content revolving around such concepts are so scarce, But you made it so clear as day. Thank you :) don't need pycharm cause VSC is nicer lol
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this is heresies, black wizardry and demonology combined
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I've not used python in years, and primarily use TypeScript myself currently. I had an alright time using Python when I did, but didn't think too much of the language, but your videos including this one really make me appreciate python more! This whole system shown in the video is very elegant imo, and very powerful.
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It's interesting to see overloading implemented in Python, I saw a stackoverflow comment suggesting to use multiple dispatch instead and now I might see why considering the slowdowns. Great video as always :) #pycharm
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I've definitely learned more from your channel than any of the other python channels, and courses I've taken combined. Please keep making such great content. #clion
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So you were trying to overload a function with the wrong syntax and didn't work, the you used the correct way to do it and worked. Mind bending.
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Awesome video! It's a bit more advanced than usual, but it's good to hear something like that once in a while!
