Method clone

dask/highlevelgraph.py:201–274

Clone selected keys in the layer, as well as references to keys in other layers Parameters ---------- keys Keys to be replaced. This never includes keys not listed by :meth:`get_output_keys`. It must also include any keys that are outside

(
        self,
        keys: set,
        seed: Hashable,
        bind_to: Key | None = None,
    )

        return keys_in_tasks(all_hlg_keys, [self[key]])

    def clone(
        self,
        keys: set,
        seed: Hashable,
        bind_to: Key | None = None,
    ) -> tuple[Layer, bool]:
        """Clone selected keys in the layer, as well as references to keys in other
        layers

        Parameters
        ----------
        keys
            Keys to be replaced. This never includes keys not listed by
            :meth:`get_output_keys`. It must also include any keys that are outside
            of this layer that may be referenced by it.
        seed
            Common hashable used to alter the keys; see :func:`dask.base.clone_key`
        bind_to
            Optional key to bind the leaf nodes to. A leaf node here is one that does
            not reference any replaced keys; in other words it's a node where the
            replacement graph traversal stops; it may still have dependencies on
            non-replaced nodes.
            A bound node will not be computed until after ``bind_to`` has been computed.

        Returns
        -------
        - New layer
        - True if the ``bind_to`` key was injected anywhere; False otherwise

        Notes
        -----
        This method should be overridden by subclasses to avoid materializing the layer.
        """
        from dask.graph_manipulation import chunks

        is_leaf: bool

        def clone_value(o):
            """Variant of distributed.utils_comm.subs_multiple, which allows injecting
            bind_to
            """
            nonlocal is_leaf

            typ = type(o)
            if typ is tuple and o and callable(o[0]):
                return (o[0],) + tuple(clone_value(i) for i in o[1:])
            elif typ is list:
                return [clone_value(i) for i in o]
            elif typ is dict:
                return {k: clone_value(v) for k, v in o.items()}
            else:
                try:
                    if o not in keys:
                        return o
                except TypeError:
                    return o
                is_leaf = False
                return clone_key(o, seed)