In this video, you’ll meet the Conditional Expression, which is some sort of one-line if-else-statement.
The basic syntax is as follows:
Python
<statement1> if <expr> else <statement2>
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Conditional Expressions
00:00 Section 4: Conditional Expressions. Conditional expressions are slightly confusing at first. They kind of look like a one-liner, but they’re written differently.
00:12
If it helps, you can think of them as a one-line if/else statement. Think back to the if/else syntax.
00:21
A conditional expression is just taking this syntax and streamlining it so it looks like this. You can see now the expression sits in the middle, <statement1> comes first if <expr> is True, or else we use <statement2>. You’ll see this most often used as a way to assign variables based on the results of a comparison.
00:48
Let’s hop into the console and I’ll show you what that looks like. We need a variable or something to compare in our conditional expression, so let’s give it dog_lover is True. And let’s set up another variable.
01:10
Let’s say you want to use a conditional expression to assign this variable, buy_a_dog. We need our first statement, which will just simply be "Yes" if dog_lover—if dog_lover evaluates to True—else "Nope", we’re not going to buy a dog.
01:36
So, see if you can work this out in your head real quick and then press Enter. Oh, I’m missing the r on dog_lover. Let’s try that again.
01:47
And now I’ll hit Up arrow twice to get back to my conditional. Now let’s see what the buy_a_dog variable contains.
01:57
We get 'Yes'. If I switch dog_lover to False and run the conditional expression again, buy_a_dog will be 'Nope'.
02:10 That’s it for conditional expressions, my friend. See you in the next one!
smohankumar7 on May 21, 2022
yes, please correct it
Martin Breuss RP Team on May 22, 2022
The lesson is updated now, thanks for the heads-up Zarata and smohankumar7 :)
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Zarata on April 7, 2020
Oops. Your one slide states:
You’re fine in the example block above this comment :)