Type hinting

[sobolevn]

I have started to use mypy. Aaaand it is not so good right now.

Libraries lack typing support. And I know that mimesis support only python3.
Do you consider adding type hints?

There are some advantages:

• stricter API
• static analysis support to improve quality

There are some disadvantages:

• type hinting was introduced in python3.5, so any version prior to that will have to use special comments or other hacks
• a lot of manual work
• possible API changes

[lk-geimfari]

Do you mean annotations?

Something like this:

def function(num: float) -> int:
    pass

Right?

[sobolevn]

Yes.

[lk-geimfari]

I thinks that we can add annotations. What about Python 3.4?

[lk-geimfari]

Seems like annotations was added in Python 3.0. And we lose nothing.

[sobolevn]

https://www.python.org/dev/peps/pep-0484/ Since 3.5

[lk-geimfari]

@sobolevn Soooo... What shall we do? Refusing to support Python 3.4 doesn't seem to be a good idea.

[sobolevn]

It actually is in some cases. Since upgrading from 3.4 to 3.5 is painless in 90% of situations.

[lk-geimfari]

@sobolevn Let's do this!

[sobolevn]

Please, note that variable annotations is not supported in 3.5. https://stackoverflow.com/questions/39971929/what-are-variable-annotations-in-python-3-6/39973133#39973133

So, we have to annotate methods and functions only.

[lk-geimfari]

@sobolevn I will add annotations for functions and methods. Can i hope for your help with situations which confuse me?

[lk-geimfari]

Example:

    def randints(self, amount: int = None, a: int = 1, b: int = 100) -> list:
        """Generate list of random integers.

        :param amount: Amount of elements.
        :param a: Minimum value of range.
        :param b: Maximum value of range.
        :return: List of random integers.
        """

        if not amount:
            amount = 3

        return [self.randint(a, b)
                for _ in range(amount)]

Is it right that amout: int = None. Is it should be integer default value or None is okay?

[lk-geimfari]

@sobolevn How to be if the function returns multiple types using? Should we use typing module?