When I heard about Duck Typing for the first time, I had to laugh.

But Python https://abs.twimg.com/emoji/v2/... draggable="false" alt="🐍" title="Schlange" aria-label="Emoji: Schlange"> has surprised me before, and this time was no exception.

This is another short thread https://abs.twimg.com/emoji/v2/... draggable="false" alt="🧵" title="Thread" aria-label="Emoji: Thread"> that will change the way you write code.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">

Here is the idea behind Duck Typing:

https://abs.twimg.com/emoji/v2/... draggable="false" alt="▫️" title="Weißes kleines Quadrat" aria-label="Emoji: Weißes kleines Quadrat">If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck.

Taking this to Python& #39;s world, the functionality of an object is more important than its type. If the object quacks, then it& #39;s a duck.

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Duck Typing is possible in dynamic languages (Hello, JavaScript fans https://abs.twimg.com/emoji/v2/... draggable="false" alt="👋" title="Waving hand" aria-label="Emoji: Waving hand">!)

Look at the attached example. Notice how "Playground" doesn& #39;t care about the specific type of the supplied item. Instead, it assumes that the item supports the bounce() method.

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To make our Playground example work, we don& #39;t need to abuse from inheritance or implement interfaces.

Duck Typing makes it possible to use whatever we need to get the work done, and we don& #39;t have to worry about a complex hierarchy of types.

Let& #39;s see other examples.

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I& #39;m sure you are familiar with len(), the function that determines how many elements are in a list.

Thanks to Duck Typing, this function will work with any class that implements a __len__() method, regardless of its type.

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The attached example uses __iter__() and __next__() to prepare our Computer class with everything it needs to work with the standard for-loop construct.

Again, no need to implement specific types. If it quacks, it& #39;s a duck.

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One thing to notice:

Duck Typing is closely related to the "It& #39;s Easier to Ask for Forgiveness than Permission" (EAFP) principle.

In case you are curious, I wrote about EAFP just yesterday:

https://twitter.com/svpino/status/1315149223176929280?s=20

https://twitter.com/svpino/st... class="Emoji" style="height:16px;" src=" https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">

https://twitter.com/svpino/status/1315149223176929280?s=20

What does this matter?

Dynamic-type advocates like myself love Duck Typing because it makes the code cleaner, explicit, and fosters reusability and flexibility without cluttering it with abstractions.

Static-type lovers have a different opinion.

But this is Python https://abs.twimg.com/emoji/v2/... draggable="false" alt="🐍" title="Schlange" aria-label="Emoji: Schlange">

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