Source code for orbax.checkpoint.experimental.v1._src.tree.types

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"""Types for PyTree utilities."""

import typing
from typing import Any, Generic, TypeVar
import jax
import numpy as np
from orbax.checkpoint._src.tree import types as tree_types
from orbax.checkpoint.experimental.v1._src.arrays import types as array_types


JsonType = tree_types.JsonType

T = TypeVar("T")

if typing.TYPE_CHECKING:
  PyTreeOf = Any
  PyTree = Any

else:



  class PyTreeOf(Generic[T]):
    """A PyTree with leaf types of type `T`.

    Functionally this type is treated as `Any` since JAX PyTrees cannot be
    identified by static type checkers.

    See https://jax.readthedocs.io/en/latest/pytrees.html for information on
    PyTrees.

    At a very high level, a PyTree is a container-like object such as a dict,
    list, or `flax.struct.dataclass`.
    The elements of these containers can be traversed as
    a nested tree using `jax.tree.*` functions.

    In a checkpointing context, tree leaves are typically arrays or scalars.
    Even though arrays are logically lists, they are treated by JAX as leaf
    nodes.

    Note that all leaf nodes are definitionally PyTrees.
    """

    pass




  class PyTree:
    """A PyTree with any leaf type (:py:class:`~.PyTreeOf[Any]`)."""

    pass



PyTreeKey = tree_types.PyTreeKey
PyTreeKeyPath = tree_types.PyTreePath

Leaf = jax.Array | np.ndarray | array_types.Scalar | str
AbstractLeaf = (
    array_types.AbstractArray
    | array_types.AbstractShardedArray
    | array_types.AbstractScalar
    | str
)

JsonType = tree_types.JsonType

PLACEHOLDER = ...