🔒 how do i type hint accepting a generator

[unborn bear]

i want to make an amoba i have 2 players and i want to make it easy to replace with a bot
i thought how generators but how do i hint that i need a generator i pass the board to and yields tuples of int, int?

[carmine meadow]

@unborn bear

Python help channel opened

Remember to:

• Ask your Python question, not if you can ask or if there's an expert who can help.
• Show a code sample as text (rather than a screenshot) and the error message, if you've got one.
• Explain what you expect to happen and what actually happens.

:warning: Do not pip install anything that isn't related to your question, especially if asked to over DMs.

Closes after a period of inactivity, or when you send !close.

[idle hill]

So, generators are just iterators, basically

and you type hint an iterator with typing.Iterator[return_value]

so you'd want

from typing import Any, Iterator

def board_gen(board: Any) -> Iterator[tuple[int, int]]:
    ...
    yield (1, 1)

Btw for type hint help I recommend https://mypy.readthedocs.io/en/stable/cheat_sheet_py3.html

(apologies, I used parens rather than square brackets for the type hint - this is now fixed)

[unborn bear]

but i pass an arg to create the generator AFTER i accepted it as an arg

i need to hint accepting it

[idle hill]

I'm feeling dumb - sorry - is the parameter itself the generator?

[unborn bear]

maybe i dont really got whats the generator the instance the function or what

[idle hill]

do you have the function you want to type hint?

that might be easier to look at

[unborn bear]

in the example i have to hint board_gen itself

[idle hill]

But I did type hint that

[unborn bear]

like Game(p1 = board_gen)

not like Game(p1 = board_gen())

[idle hill]

OK - so then that's a callable that passes in a board and returns an iterator

[unborn bear]

and ill need in the init to pass self.board to the p1

[idle hill]

from typing import Any, Iterator, Callable

class Board:
    pass

class Game:
    def __init__(self, p1):
        pass

def board_gen(board: Board) -> Iterator[tuple[int, int]]:
    ...
    yield (1, 1)

p1: Callable[[Board], Iterator[tuple[int, int]]] = board_gen
g = Game(p1 = board_gen)

[unborn bear]

whats the diff between typing.Generator and Iterator?

[zinc siren]

you really ought to use collections.abc.Generator; typing.Generator is deprecated

[idle hill]

The difference is I didn't know that existed - I just used the cheat sheets hints XD

but you can use typing.Generator as well

[zinc siren]

but Generator can receive values from yield, not just produce them

[unborn bear]

what? i didnt even know that

that may be what im looking for tho

[zinc siren]

most of the time this aspect of generators is not used

they're usually just used as fancy iterators

[unborn bear]

how do i code that accepting part?

[zinc siren]

assign the yielded value to a local variable

and then you'd have to use the send() method in the generator object

is this what you're really after though?

[unborn bear]

i have a player/bot and i could eiter pass a reference at start to the board or pass the snapshots as thair turn starts

[zinc siren]

it's best if you didn't use generators until you're sure that's what you need

[unborn bear]

passing a snapshot aka .copy() would be best bc than they cant do illegal steps

and i need to define the players ssepearatly so i can do pvp bvp bvb anything

!close

[carmine meadow]

Python help channel closed

This help channel has been closed and it's no longer possible to send messages here. If your question wasn't answered, feel free to create a new post in #1035199133436354600. To maximize your chances of getting a response, check out this guide on asking good questions.