Boolean-Perusteet
Every decision your program makes - whether to show a message, repeat a step, or validate input - relies on a Boolean: True or False. Learn how Booleans work and how regular Python values behave in conditional expressions.
What Is a Boolean?
A Boolean is a value that represents truth: True or False (note the capitalization). You'll often get Booleans from comparisons - age >= 18 yields True when the condition holds - and you'll use them directly in control flow, e.g. if is_adult:.
Truthiness in Practice
In if/while conditions, Python treats many objects as "truthy" or "falsey". Empty or zero-like values are considered false, everything else is true. This lets you write natural checks such as if items: or if name: without extra comparisons.
Common Falsey Values
False;None;0,0.0;""(empty string);- Empty containers:
[],(),{},set().
Non-empty strings are truthy - even "0" or "False".
12345678910profile_complete = True user_name = "" messages_sent = 0 if profile_complete: print("Welcome to your dashboard!") # Printed because profile is complete print(bool(user_name)) # False → no name provided yet print(bool(messages_sent)) # False → user hasn't sent any messages print(bool("ok")) # True → any non-empty string counts as valid input
1. Which value is falsey in Python?
2. What value will this code output?
3. Which if will not execute its body?
Kiitos palautteestasi!
Kysy tekoälyä
Kysy tekoälyä
Kysy mitä tahansa tai kokeile jotakin ehdotetuista kysymyksistä aloittaaksesi keskustelumme
Mahtavaa!
Completion arvosana parantunut arvoon 3.45Boolean-Perusteet
Pyyhkäise näyttääksesi valikon
Every decision your program makes - whether to show a message, repeat a step, or validate input - relies on a Boolean: True or False. Learn how Booleans work and how regular Python values behave in conditional expressions.
What Is a Boolean?
A Boolean is a value that represents truth: True or False (note the capitalization). You'll often get Booleans from comparisons - age >= 18 yields True when the condition holds - and you'll use them directly in control flow, e.g. if is_adult:.
Truthiness in Practice
In if/while conditions, Python treats many objects as "truthy" or "falsey". Empty or zero-like values are considered false, everything else is true. This lets you write natural checks such as if items: or if name: without extra comparisons.
Common Falsey Values
False;None;0,0.0;""(empty string);- Empty containers:
[],(),{},set().
Non-empty strings are truthy - even "0" or "False".
12345678910profile_complete = True user_name = "" messages_sent = 0 if profile_complete: print("Welcome to your dashboard!") # Printed because profile is complete print(bool(user_name)) # False → no name provided yet print(bool(messages_sent)) # False → user hasn't sent any messages print(bool("ok")) # True → any non-empty string counts as valid input
1. Which value is falsey in Python?
2. What value will this code output?
3. Which if will not execute its body?
Kiitos palautteestasi!
