Menu
Let say I have a dictionary stored in the variable 'v':
from typing import Dict v = { 'height': 5, 'width':14, 'depth': 3 } result = doSomething( v ) def doSomething( value:Dict[???] ): #do stuff How do I declare the dictionary type in 'doSomething'? Any ideas anyone? Your help is much appreciated :)
931
Here's how you can add type hints to our function: Add a colon and a data type after each function parameter. Add an arrow ( -> ) and a data type after the function to specify the return data type.
Specify a Variable Type Casting in python is therefore done using constructor functions: int() - constructs an integer number from an integer literal, a float literal (by rounding down to the previous whole number), or a string literal (providing the string represents a whole number)
Python has a lot of built-in functions. The type() function is used to get the type of an object. When a single argument is passed to the type() function, it returns the type of the object. Its value is the same as the object.
Type hints work best in modern Pythons. Annotations were introduced in Python 3.0, and it's possible to use type comments in Python 2.7. Still, improvements like variable annotations and postponed evaluation of type hints mean that you'll have a better experience doing type checks using Python 3.6 or even Python 3.7.
Dict takes two "arguments", the type of its keys and the type of its values. For a dict that maps strings to integers, use
def doSomething(value: Dict[str, int]): The documentation could probably be a little more explicit, though.
105
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
