PHP 7 introduces return type declarations. Which means I can now indicate the return value is a certain class, interface, array, callable or one of the newly hintable scalar types, as is possible for function parameters. function returnHello(): string { return ‘hello’; } Often it happens that a value is not always present, and that … Read more
I am practicing using type hints in Python 3.5. One of my colleague uses typing.Dict: import typing def change_bandwidths(new_bandwidths: typing.Dict, user_id: int, user_name: str) -> bool: print(new_bandwidths, user_id, user_name) return False def my_change_bandwidths(new_bandwidths: dict, user_id: int, user_name: str) ->bool: print(new_bandwidths, user_id, user_name) return True def main(): my_id, my_name = 23, “Tiras” simple_dict = {“Hello”: “Moon”} … Read more
In python 3.x, it is common to use return type annotation of a function, such as: def foo() -> str: return “bar” What is the correct annotation for the “void” type? I’m considering 3 options: def foo() -> None: not logical IMO, because None is not a type, def foo() -> type(None): using the best … Read more
Is there any correct type hint to use for a file or file-like object in Python? For example, how would I type-hint the return value of this function? def foo() -> ???: return open(‘bar’) 2 Answers 2
The following code: class Type { } function foo(Type $t) { } foo(null); failed at run time: PHP Fatal error: Argument 1 passed to foo() must not be null Why is it not allowed to pass null just like other languages? 6 Answers 6
Here is my code: function phpwtf(string $s) { echo “$s\n”; } phpwtf(“Type hinting is da bomb”); Which results in this error: Catchable fatal error: Argument 1 passed to phpwtf() must be an instance of string, string given It’s more than a little Orwellian to see PHP recognize and reject the desired type in the same … Read more
Using Python 3’s function annotations, it is possible to specify the type of items contained within a homogeneous list (or other collection) for the purpose of type hinting in PyCharm and other IDEs? A pseudo-python code example for a list of int: def my_func(l:list<int>): pass I know it’s possible using Docstring… def my_func(l): “”” :type … Read more
I’m trying to split my huge class into two; well, basically into the “main” class and a mixin with additional functions, like so: main.py file: import mymixin.py class Main(object, MyMixin): def func1(self, xxx): … mymixin.py file: class MyMixin(object): def func2(self: Main, xxx): # <— note the type hint … Now, while this works just fine, … Read more
How do I use type hints to annotate a function that returns an Iterable that always yields two values: a bool and a str? The hint Tuple[bool, str] is close, except that it limits the return value type to a tuple, not a generator or other type of iterable. I’m mostly curious because I would … Read more
Suppose I have a function: def get_some_date(some_argument: int=None) -> %datetime_or_None%: if some_argument is not None and some_argument == 1: return datetime.utcnow() else: return None How do I specify the return type for something that can be None? 2 Answers 2
