how to declare variable type, C style in python

how to declare variable type, C style in python

Starting with Python 3.6, you can declare types of variables and funtions, like this :

explicit_number: type

or for a function

def function(explicit_number: type) -> type:
    pass

This example from this post: How to Use Static Type Checking in Python 3.6 is more explicit

from typing import Dict

def get_first_name(full_name: str) -> str:
    return full_name.split( )[0]

fallback_name: Dict[str, str] = {
    first_name: UserFirstName,
    last_name: UserLastName
}

raw_name: str = input(Please enter your name: )
first_name: str = get_first_name(raw_name)

# If the user didnt type anything in, use the fallback name
if not first_name:
    first_name = get_first_name(fallback_name)

print(fHi, {first_name}!)

See the docs for the typing module

Edit: Python 3.5 introduced type hints which introduced a way to specify the type of a variable. This answer was written before this feature became available.

There is no way to declare variables in Python, since neither declaration nor variables in the C sense exist. This will bind the three names to the same object:

x = y = z = 0

how to declare variable type, C style in python

Python isnt necessarily easier/faster than C, though its possible that its simpler 😉

To clarify another statement you made, you dont have to declare the data type – it should be restated that you cant declare the data type. When you assign a value to a variable, the type of the value becomes the type of the variable. Its a subtle difference, but different nonetheless.

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