Show HN: Prisma Python – A fully typed ORM for Python

Re:Show HN: Prisma Python – A fully typed ORM for Python by samwillis on Monday February 21, 2022 @12:55PM (#30418604)

Exactly, it’a brilliant that they designed a system where the annotations themselves can be dynamic and read at runtime, it has so much potential for interesting things. But MyPy completely hobbles it by preventing all the dynamic potential, even if MyPy had an escape hatch to say ignore anything derived from this type as it’s not possible to describe statically that would be better than nothing.

It unfortunately leaves you with a choice of either taking advantage of dynamic annotations or using MyPy, but not both.

And as the sibling comment says, typescript did it so much better.

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Re:Show HN: Prisma Python – A fully typed ORM for Python by probablyrobert on Monday February 21, 2022 @01:39PM (#30419124)

There is actually an escape hatch you can use, although it is a bit clunky:

    ```py
    from typing import TYPE_CHECKING

    if TYPE_CHECKING:
        Foo = "expression that mypy can understand"
    else:
        Foo = "dynamic expression"
    ```

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Re:Show HN: Prisma Python – A fully typed ORM for Python by samwillis on Monday February 21, 2022 @01:47PM (#30419229)

Somehow in all my searching the other day I missed that, thanks!

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Re:Show HN: Prisma Python – A fully typed ORM for Python by BerislavLopac on Monday February 21, 2022 @03:42PM (#30420346)

Python also offers structural typing, which is both dynamic and mypy-compatible.

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