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Python Introducing Lists Meet Lists Addition

Bastian Petersson
Bastian Petersson
9,164 Points

Is there a way to make the list only accept one type?

Is there a way to make a list only accept one type like an array does in swift for example?

3 Answers

Cooper Runstein
Cooper Runstein
11,850 Points

Python is a dynamically typed language, this sort of functionality doesn't exist in dynamic languages. You can check and make sure your list is all of the type you wanted, but you can't enforce it as, say, a list of integers.

Jared Mollenkamp
Jared Mollenkamp
2,337 Points

You could take your input ant convert it into an intager using int("7") and use the try command for if someone puts in a letter

Sergio Andrés Herrera Velásquez
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.a{fill-rule:evenodd;}techdegree seal-36
Sergio Andrés Herrera Velásquez
Python Development Techdegree Graduate 12,788 Points

you can import from the typing module the List, it won't change the functioning or coerce the type ,but would allow you to type hint it to other developers or your future self , mostly used for documentation purposes as shown below

from typing import List def sum_integers(numbers: List[int]) -> int: total = 0 for number in numbers: total += number return total

Usage:

integers: List[int] = [1, 2, 3, 4, 5] result = sum_integers(integers) print(result) # Output: 15