What does the Zen of Python 🐍 mean by “Explicit is better than implicit.”?

The Zen of Python 🐍 says

“Explicit is better than implicit.”

This means what it says on the tin.

But “explicit” might not mean what you expect.

>>> import this
# ...
Explicit is better than implicit.
# ...

Explicit code isn't code that spells out every single step.

For example, suppose you want to sum a list of numbers.

Which of the two snippets below do you prefer?

my_list = [...]
list_sum = sum(my_list)
my_list = [...]
list_sum = 0
for number in my_list:
    list_sum += number

Well, the for loop is more explicit so it's preferred, right?

Hell NO!

We want to be explicit about the semantics of our code and not about the irrelevant details.

When you see the built-in sum being used you know immediately that we are summing a list.

On the other hand, when you see a for loop, you have to interpret it.

You have to analyse it and figure out what it's doing.

This is taxing for your brain, no matter how easy it ends up being.

Thus, making use of the built-in sum is more explicit than the for loop.

In general, if there are functions and/or modules that do what you need or want, use them!

Of course, it all depends on the context you are in and the people who work with your code...

But remember, a programmer's responsibility is to use the best tool for the job...

Therefore, if there's a function/module that really does what you needed...

Should you reinvent the wheel, or should you use it?

Probably, you should use it!

Even if others around you don't know it...

In fact, if others don't know it...

Now is a good time to learn about it!

This is a type of discussion I see myself having quite regularly.

Where do you stand on this?

In what scenarios should we not use modules that others might not know of yet?

In what scenarios should we push others to learn these new modules?


This thread ties in nicely with the Pydon't about the Zen of Python, where I go over the point of the Zen of Python as a whole.

I hope you learned something new! If you did, consider following the footsteps of the readers who bought me a slice of pizza 🍕. Your small contribution helps me produce this content for free and without spamming you with annoying ads.

Previous Post Next Post

Blog Comments powered by Disqus.