mypy-play

a = { 10 }
b = { 20 }                        
print( ( a or [] ) + ( b or [] ) )

mypy-play

a = [ 10 ]                        
b = { 20 }                        
print( ( a or [] ) + ( b or [] ) )

mypy-play

a = [ 10 ]    
b = { 20 }    
print( a + b )

mypy-play

from typing import ClassVar, Final, Self, Any


class Interface:

    # Every subclass has a _name attribute (set by __init_subclass__)
    _name: ClassVar[Final[str]]

    # Registry of subclasses

mypy-play

from typing import Iterator


def fib(n: int) -> Iterator[int]:
    a, b = 0, 1
    while a < n:
        yield a
        a, b = b, a + b

mypy-play

cond = False
print(1, *([2] if cond else []), 3)

mypy-play

from typing import Protocol, Callable


# --- workflow contracts (the only supported implementation style) ---

class SayHelloWorkflow(Protocol):
    def run(self, name: str) -> str: ...
    
    # A benefit to this class-based approach to defining workflows over the Go
    # SDK is that we can also raise type errors for missing query or signal

mypy-play

from __future__ import annotations

from dataclasses import dataclass
from typing import Protocol


# --- "generated" RPC types (pretend these come from codegen) ---

@dataclass(frozen=True)
class HelloRequest:

mypy-play

import uuid
from typing import reveal_type
x = uuid.uuid4()
reveal_type(x)

mypy-play

from typing import Any

def fn(**kwargs: dict[str, Any]):
    ...

fn(param=[1,2,3])