List Comprehension

Basic syntax

Create a new list by applying an expression to each item in an iterable.

squares = [x**2 for x in range(5)]
print(squares)  # [0, 1, 4, 9, 16]

With conditions

Add an if clause to filter items.

evens = [x for x in range(10) if x % 2 == 0]
print(evens)  # [0, 2, 4, 6, 8]

Try it yourself

Run the example below. Edit it and see what changes.

doubled = [x * 2 for x in range(5)]
print(doubled)
 

Common mistakes

• ⚠Making comprehensions too complex — keep them readable.
• ⚠Confusing list comprehension [] with generator expression ().