What’s interesting to do with booleans, and expressions that return a boolean in particular, is that we can make decisions and take different roads depending on their True or False value.

In Python we do so using the if statement:

condition = True

if condition == True:
# do something


When the condition test resolves to True, like in the above case, its block gets executed.

What is a block? A block is that part that is indented one level (4 spaces usually) on the right:

condition = True

if condition == True:
print("The condition")
print("was true")


The block can be formed by a single line, or multiple lines as well, and it ends when you move back to the previous indentation level:

condition = True

if condition == True:
print("The condition")
print("was true")

print("Outside of the if")


In combination with if you can have an else block, that’s executed if the condition test of if results to False:

condition = True

if condition == True:
print("The condition")
print("was True")
else:
print("The condition")
print("was False")


And you can have different linked if checks with elif, that’s executed if the previous check was False:

condition = True
name = "Roger"

if condition == True:
print("The condition")
print("was True")
elif name == "Roger":
print("Hello Roger")
else:
print("The condition")
print("was False")


The second block in this case is executed if condition is False, and the name variable value is “Roger”.

In a if statement you can have just one if and else checks, but multiple series of elif checks:

condition = True
name = "Roger"

if condition == True:
print("The condition")
print("was True")
elif name == "Roger":
print("Hello Roger")
elif name == "Syd":
print("Hello Syd")
elif name == "Flavio":
print("Hello Flavio")
else:
print("The condition")
print("was False")


if and else can also be used in an inline format, which lets us return a value or another based on a condition.

Example:

a = 2
result = 2 if a == 0 else 3
print(result) # 3


One more thing! ⚠️ ✋

At the end of January I will organize the Web Development Bootcamp.

It's a 10-weeks long cohort online course where I will guide you to becoming a Web Developer.

It's not "just a course". It's a big event I organize once a year.

We'll start from zero, learn the fundamentals of Web Development, HTML CSS, JavaScript, Tailwind, Git, using the command line, VS Code, GitHub, Node.js, we'll then learn React, JSX, how to use PostgreSQL, Astro, Next.js, Prisma, deploying on Netlify/DigitalOcean/Fly/Vercel and much more!

At the end of the first 10 weeks you'll know how to create web sites and web applications and I'll unlock you the 2nd phase of the Bootcamp: you will get access to a large number of projects exclusive to the Bootcamp graduates, so you can follow my instructions to build things like private areas with authentication, clones of popular sites like Twitter YouTube Reddit, create e-commerce sites, and much much more.

Because once you got the fundamentals, you only learn by working on real, exciting projects.

To find out more, visit bootcamp.dev