Source code for flowno.core.mono_node

"""
Type definitions for mono nodes in Flowno's typechecking system.

A *Mono Node* is a node that returns a single value or tuple via return statement
rather than streaming values via yield. This module defines Protocol classes
that improve typechecking specificity for different node arities.

Examples:
    >>> @node
    ... def Add(a: int, b: int) -> int:
    ...     return a + b

    >>> @node(multiple_outputs=True)
    ... def SumAndDiff(a: int, b: int):
    ...     return a + b, a - b

.. warning::

    These classes are *never* instantiated directly - they exist solely for
    static type checking.

.. admonition:: Naming Conventions

    - MonoNode: Base protocol for all mono nodes regardless of arity
    - MonoNodeX: Node with X inputs and any number of outputs
    - MonoNodeX_Y: Node with X inputs and Y outputs

.. seealso::

    - :mod:`flowno.core.streaming_node`: Type definitions for streaming nodes
"""

from abc import abstractmethod
from collections.abc import Coroutine
from types import NotImplementedType
from typing import Any, Literal, Protocol, TypeAlias, TypeVar, overload

from flowno.core.node_base import DraftNode, DraftOutputPortRef
from typing_extensions import TypeVarTuple, Unpack, override

_ReturnTupleT_co = TypeVar("_ReturnTupleT_co", covariant=True, bound=tuple[object, ...])
"""Type variable for the return type of a mono node."""

_T1_contra = TypeVar("_T1_contra", contravariant=True)
_T2_contra = TypeVar("_T2_contra", contravariant=True)
Ts = TypeVarTuple("Ts")
"""Type variable for the input types of a mono node."""

_Tout = TypeVar("_Tout", covariant=True)
_T1_co = TypeVar("_T1_co", covariant=True)
_T2_co = TypeVar("_T2_co", covariant=True)


[docs] class MonoDraftOutputPortRef(DraftOutputPortRef[_Tout]): pass
[docs] class MonoNode(Protocol[Unpack[Ts], _ReturnTupleT_co]): """Protocol for mono nodes that produce a single tuple return value. A mono node is a node that returns a single value or tuple rather than streaming values via yield statements. This class serves as the base Protocol for all mono node arities. Note: This class is never instantiated - it exists solely for typechecking. """ def __init__(self, *args: Unpack[tuple[Any, ...]]): ... def call(self, *args: Unpack[Ts]) -> Coroutine[Any, Any, _ReturnTupleT_co]: ...
[docs] class MonoNode0(DraftNode[_ReturnTupleT_co]): """A mono node with 0 inputs that returns a tuple. See MonoNode for details on the mono node protocol. """ @abstractmethod def __init__(self): ... def call(self) -> Coroutine[Any, Any, _ReturnTupleT_co]: ...
[docs] class MonoNode0_0(MonoNode0[tuple[None]]): """A mono node with 0 inputs and 0 outputs. See MonoNode for details on the mono node protocol. """ @abstractmethod def __init__(self): ... def call(self) -> Coroutine[Any, Any, tuple[None]]: ... @override def output(self, output_port: int) -> "NotImplementedType": ...
[docs] class MonoNode0_1(MonoNode0[tuple[_T1_co]]): """A mono node with 0 inputs and 1 output. See MonoNode for details on the mono node protocol. """ @abstractmethod def __init__(self): ... def call(self) -> Coroutine[Any, Any, tuple[_T1_co]]: ... @overload def output(self, output_port: Literal[0]) -> "MonoDraftOutputPortRef[_T1_co]": ... @overload def output(self, output_port: int) -> "NotImplementedType": ...
_T1_co = TypeVar("_T1_co", covariant=True) MonoNode_1: TypeAlias = DraftNode[Unpack[tuple[Any, ...]], tuple[_T1_co]]
[docs] class MonoNode1( DraftNode[_T1_contra, _ReturnTupleT_co], ): """A mono node with 1 input that returns a tuple. See MonoNode for details on the mono node protocol. """ # Python 3.10 does not allow Unpack in an *args list @abstractmethod def __init__(self, *args: Any): ... # TODO: Replace this with specific options when migrating to Python 3.11 def call(self, arg1: _T1_contra) -> Coroutine[Any, Any, _ReturnTupleT_co]: ...
[docs] class MonoNode2( DraftNode[_T1_contra, _T2_contra, _ReturnTupleT_co], ): """A mono node with 2 inputs that returns a tuple. See MonoNode for details on the mono node protocol. """ @abstractmethod def __init__(self): ... def call(self, arg1: _T1_contra, arg2: _T2_contra) -> Coroutine[Any, Any, _ReturnTupleT_co]: ...