Python Ternary — Tuple Syntax Hack

You may know the ternary operator x if c else y in Python which reads as “return x if c else return y“. But you may not know that you can also write the ternary operator in a shorter form as (y, x)[c]. Let’s dive into this concise way of hacking your own ternary operator!

Python Ternary Tuple Syntax

A shorthand form of the ternary operator is the following tuple syntax hack.

Syntax: You can use the tuple syntax (x, y)[c] consisting of a tuple (x, y) and a condition c enclosed in a square bracket. Here’s a more intuitive way to represent this tuple syntax.

(<OnFalse>, <OnTrue>)[<Condition>]
<OnTrue>The return expression of the operator in case the condition evaluates to True
<Condition>The condition that determines whether to return the <On True> or the <On False> branch.
<OnFalse>The return expression of the operator in case the condition evaluates to False
Tuple Syntax of the Ternary Operator

Exercise: Run the code and compare both ternary operators—the original and the tuple syntax hack.

In fact, the order of the <OnFalse> and <OnTrue> operands is just flipped when compared to the basic ternary operator. First, you have the branch that’s returned if the condition does NOT hold. Second, you run the branch that’s returned if the condition holds.

age = 17
print(('wtf', 'What?')[age<20])

The condition age<20 holds so the return value passed into the print() function is the <OnTrue> branch 'What?'. Don’t worry if this confuses you—you’re not alone. Let’s clarify why this tuple syntax works the way it does!

First, you create a tuple ('wtf', 'What?'). To access the first tuple value 'wtf', you’d use the standard indexing syntax ('wtf', 'What?')[0]. To access the second tuple value 'What?', you’d use the standard indexing syntax ('wtf', 'What?')[1].

Second, you create a condition age<20. You use this condition as the indexing value. You end up with either ('wtf', 'What?')[False] or ('wtf', 'What?')[True]. As you may know, the Booleans False and True are represented through integers 0 and 1 in Python. Thus, you get ('wtf', 'What?')[0] and ('wtf', 'What?')[1], respectively.

In other words: if your condition evaluates to False, you access the first tuple value. If your condition evaluates to True, you access the second tuple value.

Where to Go From Here?

Enough theory, let’s get some practice!

To become successful in coding, you need to get out there and solve real problems for real people. That’s how you can become a six-figure earner easily. And that’s how you polish the skills you really need in practice. After all, what’s the use of learning theory that nobody ever needs?

Practice projects is how you sharpen your saw in coding!

Do you want to become a code master by focusing on practical code projects that actually earn you money and solve problems for people?

Then become a Python freelance developer! It’s the best way of approaching the task of improving your Python skills—even if you are a complete beginner.

Join my free webinar “How to Build Your High-Income Skill Python” and watch how I grew my coding business online and how you can, too—from the comfort of your own home.

Join the free webinar now!