# BSD 3-Clause License; see https://github.com/scikit-hep/uproot4/blob/main/LICENSE

"""
This module defines behaviors for :doc:`uproot.behaviors.TBranch.TBranch` and
:doc:`uproot.behaviors.TBranch.HasBranches` (both ``TBranch`` and
``TTree``).

Most of the functionality of TTree-reading is implemented here.

See :doc:`uproot.models.TBranch` for deserialization of the ``TBranch``
objects themselves.
"""


import queue
import re
import sys
import threading
from collections.abc import Iterable, Mapping, MutableMapping

import numpy

import uproot
import uproot.language.python
from uproot._util import no_filter

np_uint8 = numpy.dtype("u1")


class _NoClose:
    def __init__(self, hasbranches):
        self.hasbranches = hasbranches

    def __enter__(self):
        return self

    def __exit__(self, exception_type, exception_value, traceback):
        pass

    def __getattr__(self, attr):
        return getattr(self.hasbranches, attr)

    def __getitem__(self, where):
        return self.hasbranches[where]


def iterate(
    files,
    expressions=None,
    cut=None,
    filter_name=no_filter,
    filter_typename=no_filter,
    filter_branch=no_filter,
    aliases=None,
    language=uproot.language.python.python_language,
    step_size="100 MB",
    decompression_executor=None,
    interpretation_executor=None,
    library="ak",
    how=None,
    report=False,
    custom_classes=None,
    allow_missing=False,
    **options,  # NOTE: a comma after **options breaks Python 2
):
    """
    Args:
        files: See below.
        expressions (None, str, or list of str): Names of ``TBranches`` or
            aliases to convert to arrays or mathematical expressions of them.
            Uses the ``language`` to evaluate. If None, all ``TBranches``
            selected by the filters are included.
        cut (None or str): If not None, this expression filters all of the
            ``expressions``.
        filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
            filter to select ``TBranches`` by name.
        filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
            filter to select ``TBranches`` by type.
        filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
            filter to select ``TBranches`` using the full
            :doc:`uproot.behaviors.TBranch.TBranch` object. If the function
            returns False or None, the ``TBranch`` is excluded; if the function
            returns True, it is included with its standard
            :ref:`uproot.behaviors.TBranch.TBranch.interpretation`; if an
            :doc:`uproot.interpretation.Interpretation`, this interpretation
            overrules the standard one.
        aliases (None or dict of str \u2192 str): Mathematical expressions that
            can be used in ``expressions`` or other aliases (without cycles).
            Uses the ``language`` engine to evaluate. If None, only the
            :ref:`uproot.behaviors.TBranch.TBranch.aliases` are available.
        language (:doc:`uproot.language.Language`): Language used to interpret
            the ``expressions`` and ``aliases``.
        step_size (int or str): If an integer, the maximum number of entries to
            include in each iteration step; if a string, the maximum memory size
            to include. The string must be a number followed by a memory unit,
            such as "100 MB".
        decompression_executor (None or Executor with a ``submit`` method): The
            executor that is used to decompress ``TBaskets``; if None, a
            :doc:`uproot.source.futures.TrivialExecutor` is created.
        interpretation_executor (None or Executor with a ``submit`` method): The
            executor that is used to interpret uncompressed ``TBasket`` data as
            arrays; if None, a :doc:`uproot.source.futures.TrivialExecutor`
            is created.
        library (str or :doc:`uproot.interpretation.library.Library`): The library
            that is used to represent arrays. Options are ``"np"`` for NumPy,
            ``"ak"`` for Awkward Array, and ``"pd"`` for Pandas.
        how (None, str, or container type): Library-dependent instructions
            for grouping. The only recognized container types are ``tuple``,
            ``list``, and ``dict``. Note that the container *type itself*
            must be passed as ``how``, not an instance of that type (i.e.
            ``how=tuple``, not ``how=()``).
        report (bool): If True, this generator yields
            (arrays, :doc:`uproot.behaviors.TBranch.Report`) pairs; if False,
            it only yields arrays. The report has data about the ``TFile``,
            ``TTree``, and global and local entry ranges.
        custom_classes (None or dict): If a dict, override the classes from
            the :doc:`uproot.reading.ReadOnlyFile` or ``uproot.classes``.
        allow_missing (bool): If True, skip over any files that do not contain
            the specified ``TTree``.
        options: See below.

    Iterates through contiguous chunks of entries from a set of files.

    For example:

    .. code-block:: python

        >>> for array in uproot.iterate("files*.root:tree", ["x", "y"], step_size=100):
        ...     # each of the following have 100 entries
        ...     array["x"], array["y"]

    Allowed types for the ``files`` parameter:

    * str/bytes: relative or absolute filesystem path or URL, without any colons
      other than Windows drive letter or URL schema.
      Examples: ``"rel/file.root"``, ``"C:\\abs\\file.root"``, ``"http://where/what.root"``
    * str/bytes: same with an object-within-ROOT path, separated by a colon.
      Example: ``"rel/file.root:tdirectory/ttree"``
    * pathlib.Path: always interpreted as a filesystem path or URL only (no
      object-within-ROOT path), regardless of whether there are any colons.
      Examples: ``Path("rel:/file.root")``, ``Path("/abs/path:stuff.root")``
    * glob syntax in str/bytes and pathlib.Path.
      Examples: ``Path("rel/*.root")``, ``"/abs/*.root:tdirectory/ttree"``
    * dict: keys are filesystem paths, values are objects-within-ROOT paths.
      Example: ``{{"/data_v1/*.root": "ttree_v1", "/data_v2/*.root": "ttree_v2"}}``
    * already-open TTree objects.
    * iterables of the above.

    Options (type; default):

    * file_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.file.MemmapSource`)
    * xrootd_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.xrootd.XRootDSource`)
    * http_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.http.HTTPSource`)
    * object_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.object.ObjectSource`)
    * timeout (float for HTTP, int for XRootD; 30)
    * max_num_elements (None or int; None)
    * num_workers (int; 1)
    * num_fallback_workers (int; 10)
    * begin_chunk_size (memory_size; 512)
    * minimal_ttree_metadata (bool; True)

    See also :ref:`uproot.behaviors.TBranch.HasBranches.iterate` to iterate
    within a single file.

    Other file entry points:

    * :doc:`uproot.reading.open`: opens one file to read any of its objects.
    * :doc:`uproot.behaviors.TBranch.iterate` (this function): iterates through
      chunks of contiguous entries in ``TTrees``.
    * :doc:`uproot.behaviors.TBranch.concatenate`: returns a single concatenated
      array from ``TTrees``.
    * :doc:`uproot.behaviors.TBranch.lazy`: returns a lazily read array from
      ``TTrees``.
    """
    files = uproot._util.regularize_files(files)
    decompression_executor, interpretation_executor = _regularize_executors(
        decompression_executor, interpretation_executor, None
    )
    library = uproot.interpretation.library._regularize_library(library)

    global_offset = 0
    for file_path, object_path in files:
        hasbranches = uproot._util.regularize_object_path(
            file_path, object_path, custom_classes, allow_missing, options
        )

        if hasbranches is not None:
            with hasbranches:
                try:
                    for item in hasbranches.iterate(
                        expressions=expressions,
                        cut=cut,
                        filter_name=filter_name,
                        filter_typename=filter_typename,
                        filter_branch=filter_branch,
                        aliases=aliases,
                        language=language,
                        step_size=step_size,
                        decompression_executor=decompression_executor,
                        interpretation_executor=interpretation_executor,
                        library=library,
                        how=how,
                        report=report,
                    ):
                        if report:
                            arrays, report = item
                            arrays = library.global_index(arrays, global_offset)
                            report = report.to_global(global_offset)
                            yield arrays, report
                        else:
                            arrays = library.global_index(item, global_offset)
                            yield arrays
                except uproot.exceptions.KeyInFileError:
                    if allow_missing:
                        continue
                    else:
                        raise

                global_offset += hasbranches.num_entries


def concatenate(
    files,
    expressions=None,
    cut=None,
    filter_name=no_filter,
    filter_typename=no_filter,
    filter_branch=no_filter,
    aliases=None,
    language=uproot.language.python.python_language,
    decompression_executor=None,
    interpretation_executor=None,
    library="ak",
    how=None,
    custom_classes=None,
    allow_missing=False,
    **options,  # NOTE: a comma after **options breaks Python 2
):
    """
    Args:
        files: See below.
        expressions (None, str, or list of str): Names of ``TBranches`` or
            aliases to convert to arrays or mathematical expressions of them.
            Uses the ``language`` to evaluate. If None, all ``TBranches``
            selected by the filters are included.
        cut (None or str): If not None, this expression filters all of the
            ``expressions``.
        filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
            filter to select ``TBranches`` by name.
        filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
            filter to select ``TBranches`` by type.
        filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
            filter to select ``TBranches`` using the full
            :doc:`uproot.behaviors.TBranch.TBranch` object. If the function
            returns False or None, the ``TBranch`` is excluded; if the function
            returns True, it is included with its standard
            :ref:`uproot.behaviors.TBranch.TBranch.interpretation`; if an
            :doc:`uproot.interpretation.Interpretation`, this interpretation
            overrules the standard one.
        aliases (None or dict of str \u2192 str): Mathematical expressions that
            can be used in ``expressions`` or other aliases (without cycles).
            Uses the ``language`` engine to evaluate. If None, only the
            :ref:`uproot.behaviors.TBranch.TBranch.aliases` are available.
        language (:doc:`uproot.language.Language`): Language used to interpret
            the ``expressions`` and ``aliases``.
        decompression_executor (None or Executor with a ``submit`` method): The
            executor that is used to decompress ``TBaskets``; if None, a
            :doc:`uproot.source.futures.TrivialExecutor` is created.
        interpretation_executor (None or Executor with a ``submit`` method): The
            executor that is used to interpret uncompressed ``TBasket`` data as
            arrays; if None, a :doc:`uproot.source.futures.TrivialExecutor`
            is created.
        library (str or :doc:`uproot.interpretation.library.Library`): The library
            that is used to represent arrays. Options are ``"np"`` for NumPy,
            ``"ak"`` for Awkward Array, and ``"pd"`` for Pandas.
        how (None, str, or container type): Library-dependent instructions
            for grouping. The only recognized container types are ``tuple``,
            ``list``, and ``dict``. Note that the container *type itself*
            must be passed as ``how``, not an instance of that type (i.e.
            ``how=tuple``, not ``how=()``).
        custom_classes (None or dict): If a dict, override the classes from
            the :doc:`uproot.reading.ReadOnlyFile` or ``uproot.classes``.
        allow_missing (bool): If True, skip over any files that do not contain
            the specified ``TTree``.
        options: See below.

    Returns an array with data from a set of files concatenated into one.

    For example:

    .. code-block:: python

        >>> array = uproot.concatenate("files*.root:tree", ["x", "y"])

    Depending on the number of files, the number of selected ``TBranches``, and
    the size of your computer's memory, this function might not have enough
    memory to run.

    Allowed types for the ``files`` parameter:

    * str/bytes: relative or absolute filesystem path or URL, without any colons
      other than Windows drive letter or URL schema.
      Examples: ``"rel/file.root"``, ``"C:\\abs\\file.root"``, ``"http://where/what.root"``
    * str/bytes: same with an object-within-ROOT path, separated by a colon.
      Example: ``"rel/file.root:tdirectory/ttree"``
    * pathlib.Path: always interpreted as a filesystem path or URL only (no
      object-within-ROOT path), regardless of whether there are any colons.
      Examples: ``Path("rel:/file.root")``, ``Path("/abs/path:stuff.root")``
    * glob syntax in str/bytes and pathlib.Path.
      Examples: ``Path("rel/*.root")``, ``"/abs/*.root:tdirectory/ttree"``
    * dict: keys are filesystem paths, values are objects-within-ROOT paths.
      Example: ``{{"/data_v1/*.root": "ttree_v1", "/data_v2/*.root": "ttree_v2"}}``
    * already-open TTree objects.
    * iterables of the above.

    Options (type; default):

    * file_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.file.MemmapSource`)
    * xrootd_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.xrootd.XRootDSource`)
    * http_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.http.HTTPSource`)
    * object_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.object.ObjectSource`)
    * timeout (float for HTTP, int for XRootD; 30)
    * max_num_elements (None or int; None)
    * num_workers (int; 1)
    * num_fallback_workers (int; 10)
    * begin_chunk_size (memory_size; 512)
    * minimal_ttree_metadata (bool; True)

    Other file entry points:

    * :doc:`uproot.reading.open`: opens one file to read any of its objects.
    * :doc:`uproot.behaviors.TBranch.iterate`: iterates through chunks of
      contiguous entries in ``TTrees``.
    * :doc:`uproot.behaviors.TBranch.concatenate` (this function): returns a
      single concatenated array from ``TTrees``.
    * :doc:`uproot.behaviors.TBranch.lazy`: returns a lazily read array from
      ``TTrees``.
    """
    files = uproot._util.regularize_files(files)
    decompression_executor, interpretation_executor = _regularize_executors(
        decompression_executor, interpretation_executor, None
    )
    library = uproot.interpretation.library._regularize_library(library)

    all_arrays = []
    global_start = 0
    for file_path, object_path in files:
        hasbranches = uproot._util.regularize_object_path(
            file_path, object_path, custom_classes, allow_missing, options
        )
        if hasbranches is not None:
            with hasbranches:
                try:
                    arrays = hasbranches.arrays(
                        expressions=expressions,
                        cut=cut,
                        filter_name=filter_name,
                        filter_typename=filter_typename,
                        filter_branch=filter_branch,
                        aliases=aliases,
                        language=language,
                        decompression_executor=decompression_executor,
                        interpretation_executor=interpretation_executor,
                        array_cache=None,
                        library=library,
                        how=how,
                    )
                    arrays = library.global_index(arrays, global_start)
                except uproot.exceptions.KeyInFileError:
                    if allow_missing:
                        continue
                    else:
                        raise

                all_arrays.append(arrays)
                global_start += hasbranches.num_entries

    return library.concatenate(all_arrays)


def lazy(
    files,
    filter_name=no_filter,
    filter_typename=no_filter,
    filter_branch=no_filter,
    recursive=True,
    full_paths=False,
    step_size="100 MB",
    decompression_executor=None,
    interpretation_executor=None,
    array_cache="100 MB",
    library="ak",
    custom_classes=None,
    allow_missing=False,
    **options,  # NOTE: a comma after **options breaks Python 2
):
    """
    Args:
        files: See below.
        filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
            filter to select ``TBranches`` by name.
        filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
            filter to select ``TBranches`` by type.
        filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
            filter to select ``TBranches`` using the full
            :doc:`uproot.behaviors.TBranch.TBranch` object. If the function
            returns False or None, the ``TBranch`` is excluded; if the function
            returns True, it is included with its standard
            :ref:`uproot.behaviors.TBranch.TBranch.interpretation`; if an
            :doc:`uproot.interpretation.Interpretation`, this interpretation
            overrules the standard one.
        recursive (bool): If True, include all subbranches of branches as
            separate fields; otherwise, only search one level deep.
        full_paths (bool): If True, include the full path to each subbranch
            with slashes (``/``); otherwise, use the descendant's name as
            the field name.
        step_size (int or str): If an integer, the maximum number of entries to
            include in each iteration step; if a string, the maximum memory size
            to include. The string must be a number followed by a memory unit,
            such as "100 MB".
        decompression_executor (None or Executor with a ``submit`` method): The
            executor that is used to decompress ``TBaskets``; if None, a
            :doc:`uproot.source.futures.TrivialExecutor` is created.
        interpretation_executor (None or Executor with a ``submit`` method): The
            executor that is used to interpret uncompressed ``TBasket`` data as
            arrays; if None, a :doc:`uproot.source.futures.TrivialExecutor`
            is created.
        array_cache (None, MutableMapping, or memory size): Cache of arrays;
            if None, do not use a cache; if a memory size, create a new cache
            of this size.
        library (str or :doc:`uproot.interpretation.library.Library`): The library
            that is used to represent arrays. For lazy arrays, only ``"ak"``
            for Awkward Array is allowed.
        custom_classes (None or dict): If a dict, override the classes from
            the :doc:`uproot.reading.ReadOnlyFile` or ``uproot.classes``.
        allow_missing (bool): If True, skip over any files that do not contain
            the specified ``TTree``.
        options: See below.

    Returns a lazy array, which loads data on demand. Only the files and
    ``TTree`` metadata are opened when this function is invoked.

    For example:

    .. code-block:: python

        >>> lazyarray = uproot.lazy("files*.root:tree")
        >>> # all files*.root have been opened and the "tree" from each is examined

        >>> lazyarray
        <Array [{Type: 'GT', Run: 148031, ... M: 96.7}] type='23047295 * {"Type": string...'>
        >>> # the first TBasket of "Type" and "Run" have now been read, as well as the last
        >>> # TBasket of "M", to print these values on the screen.

        >>> np.sqrt(lazyarray.px1**2 + lazyarray.py1**2)
        <Array [44.7, 38.8, 38.8, ... 32.4, 32.4, 32.5] type='23047295 * float64'>
        >>> # the entirety of "px1" and "py1" have now been read, to perform a calculation.

    If the size of the fields used in a calculation do not fit into ``array_cache``,
    lazy arrays may be inefficient, repeatedly rereading data that could be read
    once by iterating through the calculation with
    :doc:`uproot.behaviors.TBranch.iterate`.

    Allowed types for the ``files`` parameter:

    * str/bytes: relative or absolute filesystem path or URL, without any colons
      other than Windows drive letter or URL schema.
      Examples: ``"rel/file.root"``, ``"C:\\abs\\file.root"``, ``"http://where/what.root"``
    * str/bytes: same with an object-within-ROOT path, separated by a colon.
      Example: ``"rel/file.root:tdirectory/ttree"``
    * pathlib.Path: always interpreted as a filesystem path or URL only (no
      object-within-ROOT path), regardless of whether there are any colons.
      Examples: ``Path("rel:/file.root")``, ``Path("/abs/path:stuff.root")``
    * glob syntax in str/bytes and pathlib.Path.
      Examples: ``Path("rel/*.root")``, ``"/abs/*.root:tdirectory/ttree"``
    * dict: keys are filesystem paths, values are objects-within-ROOT paths.
      Example: ``{{"/data_v1/*.root": "ttree_v1", "/data_v2/*.root": "ttree_v2"}}``
    * already-open TTree objects.
    * iterables of the above.

    Options (type; default):

    * file_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.file.MemmapSource`)
    * xrootd_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.xrootd.XRootDSource`)
    * http_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.http.HTTPSource`)
    * object_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.object.ObjectSource`)
    * timeout (float for HTTP, int for XRootD; 30)
    * max_num_elements (None or int; None)
    * num_workers (int; 1)
    * num_fallback_workers (int; 10)
    * begin_chunk_size (memory_size; 512)
    * minimal_ttree_metadata (bool; True)

    Other file entry points:

    * :doc:`uproot.reading.open`: opens one file to read any of its objects.
    * :doc:`uproot.behaviors.TBranch.iterate`: iterates through chunks of
      contiguous entries in ``TTrees``.
    * :doc:`uproot.behaviors.TBranch.concatenate`: returns a single
      concatenated array from ``TTrees``.
    * :doc:`uproot.behaviors.TBranch.lazy` (this function): returns a lazily
      read array from ``TTrees``.
    """
    awkward = uproot.extras.awkward()
    files = uproot._util.regularize_files(files)
    decompression_executor, interpretation_executor = _regularize_executors(
        decompression_executor, interpretation_executor, None
    )
    array_cache = _regularize_array_cache(array_cache, None)
    library = uproot.interpretation.library._regularize_library_lazy(library)

    hold_cache = array_cache
    if array_cache is not None and not isinstance(
        array_cache, awkward.layout.ArrayCache
    ):
        if type(array_cache) is dict:
            hold_cache = _WrapDict(array_cache)
        if not isinstance(hold_cache, MutableMapping):
            raise TypeError("array_cache must be None or a MutableMapping")
        array_cache = awkward.layout.ArrayCache(hold_cache)

    real_options = dict(options)
    if "num_workers" not in real_options:
        real_options["num_workers"] = 1
    if "num_fallback_workers" not in real_options:
        real_options["num_fallback_workers"] = 1

    filter_branch = uproot._util.regularize_filter(filter_branch)

    hasbranches = []
    common_keys = None
    is_self = []

    count = 0
    for file_path, object_path in files:
        obj = uproot._util.regularize_object_path(
            file_path, object_path, custom_classes, allow_missing, real_options
        )

        if obj is not None:
            count += 1

            if isinstance(obj, TBranch) and len(obj.keys(recursive=True)) == 0:
                original = obj
                obj = obj.parent
                is_self.append(True)

                def real_filter_branch(branch):
                    return branch is original and filter_branch(branch)  # noqa: B023

            else:
                is_self.append(False)
                real_filter_branch = filter_branch

            hasbranches.append(obj)

            new_keys = obj.keys(
                recursive=recursive,
                filter_name=filter_name,
                filter_typename=filter_typename,
                filter_branch=real_filter_branch,
                full_paths=full_paths,
            )

            if common_keys is None:
                common_keys = new_keys
            else:
                new_keys = set(new_keys)
                common_keys = [key for key in common_keys if key in new_keys]

    if count == 0:
        raise ValueError(
            "allow_missing=True and no TTrees found in\n\n    {}".format(
                "\n    ".join(
                    "{"
                    + "{}: {}".format(
                        repr(f.file_path if isinstance(f, HasBranches) else f),
                        repr(f.object_path if isinstance(f, HasBranches) else o),
                    )
                    + "}"
                    for f, o in files
                )
            )
        )

    if len(common_keys) == 0 or not (all(is_self) or not any(is_self)):
        raise ValueError(
            "TTrees in\n\n    {}\n\nhave no TBranches in common".format(
                "\n    ".join(
                    "{"
                    + "{}: {}".format(
                        repr(f.file_path if isinstance(f, HasBranches) else f),
                        repr(f.object_path if isinstance(f, HasBranches) else o),
                    )
                    + "}"
                    for f, o in files
                )
            )
        )

    partitions = []
    global_offsets = [0]
    global_cache_key = []
    for obj in hasbranches:
        entry_start, entry_stop = _regularize_entries_start_stop(
            obj.tree.num_entries, None, None
        )
        branchid_interpretation = {}
        for key in common_keys:
            branch = obj[key]
            branchid_interpretation[branch.cache_key] = branch.interpretation
        entry_step = _regularize_step_size(
            obj, step_size, entry_start, entry_stop, branchid_interpretation
        )

        def foreach(start):
            stop = min(start + entry_step, entry_stop)  # noqa: B023
            length = stop - start

            fields = []
            names = []
            for key in common_keys:
                branch = obj[key]  # noqa: B023

                interpretation = branchid_interpretation[branch.cache_key]  # noqa: B023
                form = interpretation.awkward_form(
                    obj.file,  # noqa: B023
                    {
                        "index_format": "i64",
                        "header": False,
                        "tobject_header": True,
                        "breadcrumbs": (),
                    },
                )
                form = uproot._util.recursively_fix_awkward_form_of_iter(
                    awkward, interpretation, form
                )

                generator = awkward.layout.ArrayGenerator(
                    branch.array,  # noqa: B023
                    (
                        None,
                        start,
                        stop,
                        decompression_executor,
                        interpretation_executor,
                        None,
                        "ak",
                    ),
                    {},
                    uproot._util.awkward_form_remove_uproot(
                        awkward, form
                    ),  # , interpretation
                    length,
                )
                cache_key = "{}:{}:{}-{}:{}".format(
                    branch.cache_key,  # noqa: B023
                    interpretation.cache_key,
                    start,
                    stop,
                    library.name,
                )
                global_cache_key.append(cache_key)
                virtualarray = awkward.layout.VirtualArray(
                    generator, cache=array_cache, cache_key=cache_key
                )
                fields.append(virtualarray)
                names.append(key)  # noqa: B023

            recordarray = awkward.layout.RecordArray(fields, names, length)
            partitions.append(recordarray)
            global_offsets.append(global_offsets[-1] + length)

        for start in range(entry_start, entry_stop, entry_step):
            foreach(start)

    if len(partitions) == 0:
        obj = hasbranches[0]
        entry_start, entry_stop = _regularize_entries_start_stop(
            obj.tree.num_entries, None, None
        )
        branchid_interpretation = {}
        for key in common_keys:
            branch = obj[key]
            branchid_interpretation[branch.cache_key] = branch.interpretation
        entry_step = _regularize_step_size(
            obj, step_size, entry_start, entry_stop, branchid_interpretation
        )

        foreach(0)

    out = awkward.partition.IrregularlyPartitionedArray(partitions, global_offsets[1:])
    return awkward.Array(out)


def dask(
    files,
    filter_name=no_filter,
    filter_typename=no_filter,
    filter_branch=no_filter,
    recursive=True,
    full_paths=False,
    step_size="100 MB",
    library="np",
    custom_classes=None,
    allow_missing=False,
    open_files=True,
    **options,  # NOTE: a comma after **options breaks Python 2
):
    """
    Args:
        files: See below.
        filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
            filter to select ``TBranches`` by name.
        filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
            filter to select ``TBranches`` by type.
        filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
            filter to select ``TBranches`` using the full
            :doc:`uproot.behaviors.TBranch.TBranch` object. If the function
            returns False or None, the ``TBranch`` is excluded; if the function
            returns True, it is included with its standard
            :ref:`uproot.behaviors.TBranch.TBranch.interpretation`; if an
            :doc:`uproot.interpretation.Interpretation`, this interpretation
            overrules the standard one.
        recursive (bool): If True, include all subbranches of branches as
            separate fields; otherwise, only search one level deep.
        full_paths (bool): If True, include the full path to each subbranch
            with slashes (``/``); otherwise, use the descendant's name as
            the field name.
        step_size (int or str): If an integer, the maximum number of entries to
            include in each chunk; if a string, the maximum memory_size to include
            in each chunk. The string must be a number followed by a memory unit,
            such as "100 MB".
        library (str or :doc:`uproot.interpretation.library.Library`): The library
            that is used to represent arrays.
        custom_classes (None or dict): If a dict, override the classes from
            the :doc:`uproot.reading.ReadOnlyFile` or ``uproot.classes``.
        allow_missing (bool): If True, skip over any files that do not contain
            the specified ``TTree``.
        options: See below.

    Returns dask equivalents of the backends supported by uproot.

    Allowed types for the ``files`` parameter:

    * str/bytes: relative or absolute filesystem path or URL, without any colons
      other than Windows drive letter or URL schema.
      Examples: ``"rel/file.root"``, ``"C:\\abs\\file.root"``, ``"http://where/what.root"``
    * str/bytes: same with an object-within-ROOT path, separated by a colon.
      Example: ``"rel/file.root:tdirectory/ttree"``
    * pathlib.Path: always interpreted as a filesystem path or URL only (no
      object-within-ROOT path), regardless of whether there are any colons.
      Examples: ``Path("rel:/file.root")``, ``Path("/abs/path:stuff.root")``
    * glob syntax in str/bytes and pathlib.Path.
      Examples: ``Path("rel/*.root")``, ``"/abs/*.root:tdirectory/ttree"``
    * dict: keys are filesystem paths, values are objects-within-ROOT paths.
      Example: ``{{"/data_v1/*.root": "ttree_v1", "/data_v2/*.root": "ttree_v2"}}``
    * already-open TTree objects.
    * iterables of the above.

    Options (type; default):

    * file_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.file.MemmapSource`)
    * xrootd_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.xrootd.XRootDSource`)
    * http_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.http.HTTPSource`)
    * object_handler (:doc:`uproot.source.chunk.Source` class; :doc:`uproot.source.object.ObjectSource`)
    * timeout (float for HTTP, int for XRootD; 30)
    * max_num_elements (None or int; None)
    * num_workers (int; 1)
    * num_fallback_workers (int; 10)
    * begin_chunk_size (memory_size; 512)
    * minimal_ttree_metadata (bool; True)

    Other file entry points:

    * :doc:`uproot.reading.open`: opens one file to read any of its objects.
    * :doc:`uproot.behaviors.TBranch.iterate`: iterates through chunks of
      contiguous entries in ``TTrees``.
    * :doc:`uproot.behaviors.TBranch.concatenate`: returns a single
      concatenated array from ``TTrees``.
    * :doc:`uproot.behaviors.TBranch.lazy` (this function): returns a lazily
      read array from ``TTrees``.
    """
    files = uproot._util.regularize_files(files)
    library = uproot.interpretation.library._regularize_library(library)
    if library.name != "np":
        raise NotImplementedError()

    real_options = dict(options)
    if "num_workers" not in real_options:
        real_options["num_workers"] = 1
    if "num_fallback_workers" not in real_options:
        real_options["num_fallback_workers"] = 1

    filter_branch = uproot._util.regularize_filter(filter_branch)

    if open_files:
        return _get_dask_array(
            files,
            filter_name,
            filter_typename,
            filter_branch,
            recursive,
            full_paths,
            step_size,
            custom_classes,
            allow_missing,
            real_options,
        )
    else:
        return _get_dask_array_delay_open(
            files,
            filter_name,
            filter_typename,
            filter_branch,
            recursive,
            full_paths,
            custom_classes,
            allow_missing,
            real_options,
        )


class Report:
    """
    Args:
        source (:doc:`uproot.behaviors.TBranch.HasBranches`): The
            object (:doc:`uproot.behaviors.TBranch.TBranch` or
            :doc:`uproot.behaviors.TTree.TTree`) that this batch of data
            came from.
        tree_entry_start (int): First entry in the batch, counting zero at
            the start of the current ``TTree`` (current file).
        tree_entry_stop (int): First entry *after* the batch (last entry plus
            one), counting zero at the start of the ``TTree`` (current file).
        global_offset (int): Number of entries between the start of iteration
            and the start of this ``TTree``. The
            :ref:`uproot.behaviors.TBranch.Report.global_entry_start` and
            :ref:`uproot.behaviors.TBranch.Report.global_entry_stop` are
            equal to :ref:`uproot.behaviors.TBranch.Report.tree_entry_start`
            and :ref:`uproot.behaviors.TBranch.Report.tree_entry_stop` plus
            ``global_offset``.

    Information about the current iteration of
    :ref:`uproot.behaviors.TBranch.HasBranches.iterate` (the method) or
    :doc:`uproot.behaviors.TBranch.iterate` (the function).

    Since the :ref:`uproot.behaviors.TBranch.HasBranches.iterate` method
    only iterates over data from one ``TTree``, its ``global_offset`` is always
    zero; :ref:`uproot.behaviors.TBranch.Report.global_entry_start` and
    :ref:`uproot.behaviors.TBranch.Report.global_entry_stop` are equal to
    :ref:`uproot.behaviors.TBranch.Report.tree_entry_start` and
    :ref:`uproot.behaviors.TBranch.Report.tree_entry_stop`, respectively.

    """

    def __init__(self, source, tree_entry_start, tree_entry_stop, global_offset=0):
        self._source = source
        self._tree_entry_start = tree_entry_start
        self._tree_entry_stop = tree_entry_stop
        self._global_offset = global_offset

    def __repr__(self):
        return "<Report start={} stop={} source={}>".format(
            self.global_entry_start,
            self.global_entry_stop,
            repr(self._source.file.file_path + ":" + self._source.object_path),
        )

    @property
    def source(self):
        """
        The object (:doc:`uproot.behaviors.TBranch.TBranch` or
        :doc:`uproot.behaviors.TTree.TTree`) that this batch of data
        came from.
        """
        return self._source

    @property
    def tree(self):
        """
        The :doc:`uproot.behaviors.TTree.TTree` that this batch of data
        came from.
        """
        return self._source.tree

    @property
    def file(self):
        """
        The :doc:`uproot.reading.ReadOnlyFile` that this batch of data
        came from.
        """
        return self._source.file

    @property
    def file_path(self):
        """
        The path/name of the :doc:`uproot.reading.ReadOnlyFile` that
        this batch of data came from.
        """
        return self._source.file.file_path

    @property
    def tree_entry_start(self):
        """
        First entry in the batch, counting zero at the start of the current
        ``TTree`` (current file).
        """
        return self._tree_entry_start

    @property
    def tree_entry_stop(self):
        """
        First entry *after* the batch (last entry plus one), counting zero at
        the start of the ``TTree`` (current file).
        """
        return self._tree_entry_stop

    @property
    def global_entry_start(self):
        """
        First entry in the batch, counting zero at the start of iteration
        (potentially over many files).
        """
        return self._tree_entry_start + self._global_offset

    @property
    def global_entry_stop(self):
        """
        First entry *after* the batch (last entry plust one), counting zero at
        the start of iteration (potentially over many files).
        """
        return self._tree_entry_stop + self._global_offset

    @property
    def start(self):
        """
        A synonym for
        :ref:`uproot.behaviors.TBranch.Report.global_entry_start`.
        """
        return self._tree_entry_start + self._global_offset

    @property
    def stop(self):
        """
        A synonym for
        :ref:`uproot.behaviors.TBranch.Report.global_entry_stop`.
        """
        return self._tree_entry_stop + self._global_offset

    @property
    def global_offset(self):
        """
        Number of entries between the start of iteration and the start of this
        ``TTree``. The
        :ref:`uproot.behaviors.TBranch.Report.global_entry_start` and
        :ref:`uproot.behaviors.TBranch.Report.global_entry_stop` are
        equal to :ref:`uproot.behaviors.TBranch.Report.tree_entry_start`
        and :ref:`uproot.behaviors.TBranch.Report.tree_entry_stop` plus
        ``global_offset``.
        """
        return self._global_offset

    def to_global(self, global_offset):
        """
        Copies the data in this :doc:`uproot.behaviors.TBranch.Report` to
        another with a new
        :ref:`uproot.behaviors.TBranch.Report.global_offset`.
        """
        return Report(
            self._source, self._tree_entry_start, self._tree_entry_stop, global_offset
        )


class HasBranches(Mapping):
    """
    Abstract class of behaviors for anything that "has branches," namely
    :doc:`uproot.behaviors.TTree.TTree` and
    :doc:`uproot.behaviors.TBranch.TBranch`, which mostly consist of array-reading
    methods.

    A :doc:`uproot.behaviors.TBranch.HasBranches` is a Python ``Mapping``, which
    uses square bracket syntax to extract subbranches:

    .. code-block:: python

        my_tree["branch"]
        my_tree["branch"]["subbranch"]
        my_tree["branch/subbranch"]
        my_tree["branch/subbranch/subsubbranch"]
    """

    @property
    def branches(self):
        """
        The list of :doc:`uproot.behaviors.TBranch.TBranch` directly under
        this :doc:`uproot.behaviors.TTree.TTree` or
        :doc:`uproot.behaviors.TBranch.TBranch` (i.e. not recursive).
        """
        return self.member("fBranches")

    def show(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
        full_paths=True,
        name_width=20,
        typename_width=24,
        interpretation_width=30,
        stream=sys.stdout,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, recursively descend into the branches'
                branches.
            full_paths (bool): If True, include the full path to each subbranch
                with slashes (``/``); otherwise, use the descendant's name as
                the display name.
            name_width (int): Number of characters to reserve for the ``TBranch``
                names.
            typename_width (int): Number of characters to reserve for the C++
                typenames.
            interpretation_width (int): Number of characters to reserve for the
                :doc:`uproot.interpretation.Interpretation` displays.
            stream (object with a ``write(str)`` method): Stream to write the
                output to.

        Interactively display the ``TBranches``.

        For example,

        .. code-block::

            name                 | typename             | interpretation
            ---------------------+----------------------+-----------------------------------
            event_number         | int32_t              | AsDtype('>i4')
            trigger_isomu24      | bool                 | AsDtype('bool')
            eventweight          | float                | AsDtype('>f4')
            MET                  | TVector2             | AsStridedObjects(Model_TVector2_v3
            jetp4                | std::vector<TLorentz | AsJagged(AsStridedObjects(Model_TL
            jetbtag              | std::vector<float>   | AsJagged(AsDtype('>f4'), header_by
            jetid                | std::vector<bool>    | AsJagged(AsDtype('bool'), header_b
        """
        if name_width < 3:
            raise ValueError("'name_width' must be at least 3")
        if typename_width < 3:
            raise ValueError("'typename_width' must be at least 3")
        if interpretation_width < 3:
            raise ValueError("'interpretation_width' must be at least 3")

        formatter = "{{0:{0}.{0}}} | {{1:{1}.{1}}} | {{2:{2}.{2}}}".format(
            name_width,
            typename_width,
            interpretation_width,
        )

        stream.write(formatter.format("name", "typename", "interpretation"))
        stream.write(
            "\n"
            + "-" * name_width
            + "-+-"
            + "-" * typename_width
            + "-+-"
            + "-" * interpretation_width
            + "\n"
        )

        if isinstance(self, TBranch):
            stream.write(
                formatter.format(self.name, self.typename, repr(self.interpretation))
                + "\n"
            )

        for name, branch in self.iteritems(
            filter_name=filter_name,
            filter_typename=filter_typename,
            filter_branch=filter_branch,
            recursive=recursive,
            full_paths=full_paths,
        ):
            typename = branch.typename
            interp = repr(branch.interpretation)

            if len(name) > name_width:
                name = name[: name_width - 3] + "..."
            if len(typename) > typename_width:
                typename = typename[: typename_width - 3] + "..."
            if len(interp) > interpretation_width:
                interp = interp[: interpretation_width - 3] + "..."

            stream.write(formatter.format(name, typename, interp).rstrip(" ") + "\n")

    def arrays(
        self,
        expressions=None,
        cut=None,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        aliases=None,
        language=uproot.language.python.python_language,
        entry_start=None,
        entry_stop=None,
        decompression_executor=None,
        interpretation_executor=None,
        array_cache="inherit",
        library="ak",
        how=None,
    ):
        """
        Args:
            expressions (None, str, or list of str): Names of ``TBranches`` or
                aliases to convert to arrays or mathematical expressions of them.
                Uses the ``language`` to evaluate. If None, all ``TBranches``
                selected by the filters are included.
            cut (None or str): If not None, this expression filters all of the
                ``expressions``.
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. If the function
                returns False or None, the ``TBranch`` is excluded; if the function
                returns True, it is included with its standard
                :ref:`uproot.behaviors.TBranch.TBranch.interpretation`; if an
                :doc:`uproot.interpretation.Interpretation`, this interpretation
                overrules the standard one.
            aliases (None or dict of str \u2192 str): Mathematical expressions that
                can be used in ``expressions`` or other aliases (without cycles).
                Uses the ``language`` engine to evaluate. If None, only the
                :ref:`uproot.behaviors.TBranch.TBranch.aliases` are available.
            language (:doc:`uproot.language.Language`): Language used to interpret
                the ``expressions`` and ``aliases``.
            entry_start (None or int): The first entry to include. If None, start
                at zero. If negative, count from the end, like a Python slice.
            entry_stop (None or int): The first entry to exclude (i.e. one greater
                than the last entry to include). If None, stop at
                :ref:`uproot.behaviors.TTree.TTree.num_entries`. If negative,
                count from the end, like a Python slice.
            decompression_executor (None or Executor with a ``submit`` method): The
                executor that is used to decompress ``TBaskets``; if None, the
                file's :ref:`uproot.reading.ReadOnlyFile.decompression_executor`
                is used.
            interpretation_executor (None or Executor with a ``submit`` method): The
                executor that is used to interpret uncompressed ``TBasket`` data as
                arrays; if None, the file's :ref:`uproot.reading.ReadOnlyFile.interpretation_executor`
                is used.
            array_cache ("inherit", None, MutableMapping, or memory size): Cache of arrays;
                if "inherit", use the file's cache; if None, do not use a cache;
                if a memory size, create a new cache of this size.
            library (str or :doc:`uproot.interpretation.library.Library`): The library
                that is used to represent arrays. Options are ``"np"`` for NumPy,
                ``"ak"`` for Awkward Array, and ``"pd"`` for Pandas.
            how (None, str, or container type): Library-dependent instructions
                for grouping. The only recognized container types are ``tuple``,
                ``list``, and ``dict``. Note that the container *type itself*
                must be passed as ``how``, not an instance of that type (i.e.
                ``how=tuple``, not ``how=()``).

        Returns a group of arrays from the ``TTree``.

        For example:

        .. code-block:: python

            >>> my_tree["x"].array()
            <Array [-41.2, 35.1, 35.1, ... 32.4, 32.5] type='2304 * float64'>
            >>> my_tree["y"].array()
            <Array [17.4, -16.6, -16.6, ... 1.2, 1.2, 1.2] type='2304 * float64'>

        See also :ref:`uproot.behaviors.TBranch.TBranch.array` to read a single
        ``TBranch`` as an array.

        See also :ref:`uproot.behaviors.TBranch.HasBranches.iterate` to iterate over
        the array in contiguous ranges of entries.
        """
        keys = _keys_deep(self)
        if isinstance(self, TBranch) and expressions is None and len(keys) == 0:
            filter_branch = uproot._util.regularize_filter(filter_branch)
            return self.parent.arrays(
                expressions=expressions,
                cut=cut,
                filter_name=filter_name,
                filter_typename=filter_typename,
                filter_branch=lambda branch: branch is self and filter_branch(branch),
                aliases=aliases,
                language=language,
                entry_start=entry_start,
                entry_stop=entry_stop,
                decompression_executor=decompression_executor,
                interpretation_executor=interpretation_executor,
                array_cache=array_cache,
                library=library,
                how=how,
            )

        entry_start, entry_stop = _regularize_entries_start_stop(
            self.tree.num_entries, entry_start, entry_stop
        )
        decompression_executor, interpretation_executor = _regularize_executors(
            decompression_executor, interpretation_executor, self._file
        )
        array_cache = _regularize_array_cache(array_cache, self._file)
        library = uproot.interpretation.library._regularize_library(library)

        def get_from_cache(branchname, interpretation):
            if array_cache is not None:
                cache_key = "{}:{}:{}:{}-{}:{}".format(
                    self.cache_key,
                    branchname,
                    interpretation.cache_key,
                    entry_start,
                    entry_stop,
                    library.name,
                )
                return array_cache.get(cache_key)
            else:
                return None

        aliases = _regularize_aliases(self, aliases)
        arrays, expression_context, branchid_interpretation = _regularize_expressions(
            self,
            expressions,
            cut,
            filter_name,
            filter_typename,
            filter_branch,
            keys,
            aliases,
            language,
            get_from_cache,
        )

        ranges_or_baskets = []
        checked = set()
        for _, context in expression_context:
            for branch in context["branches"]:
                if branch.cache_key not in checked:
                    checked.add(branch.cache_key)
                    for (
                        basket_num,
                        range_or_basket,
                    ) in branch.entries_to_ranges_or_baskets(entry_start, entry_stop):
                        ranges_or_baskets.append((branch, basket_num, range_or_basket))

        _ranges_or_baskets_to_arrays(
            self,
            ranges_or_baskets,
            branchid_interpretation,
            entry_start,
            entry_stop,
            decompression_executor,
            interpretation_executor,
            library,
            arrays,
            False,
        )

        # no longer needed; save memory
        del ranges_or_baskets

        _fix_asgrouped(
            arrays, expression_context, branchid_interpretation, library, how
        )

        if array_cache is not None:
            checked = set()
            for expression, context in expression_context:
                for branch in context["branches"]:
                    if branch.cache_key not in checked:
                        checked.add(branch.cache_key)
                        interpretation = branchid_interpretation[branch.cache_key]
                        if branch is not None:
                            cache_key = "{}:{}:{}:{}-{}:{}".format(
                                self.cache_key,
                                expression,
                                interpretation.cache_key,
                                entry_start,
                                entry_stop,
                                library.name,
                            )
                        array_cache[cache_key] = arrays[branch.cache_key]

        output = language.compute_expressions(
            self,
            arrays,
            expression_context,
            keys,
            aliases,
            self.file.file_path,
            self.object_path,
        )

        # no longer needed; save memory
        del arrays

        expression_context = [
            (e, c) for e, c in expression_context if c["is_primary"] and not c["is_cut"]
        ]

        return library.group(output, expression_context, how)

    def iterate(
        self,
        expressions=None,
        cut=None,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        aliases=None,
        language=uproot.language.python.python_language,
        entry_start=None,
        entry_stop=None,
        step_size="100 MB",
        decompression_executor=None,
        interpretation_executor=None,
        library="ak",
        how=None,
        report=False,
    ):
        """
        Args:
            expressions (None, str, or list of str): Names of ``TBranches`` or
                aliases to convert to arrays or mathematical expressions of them.
                Uses the ``language`` to evaluate. If None, all ``TBranches``
                selected by the filters are included.
            cut (None or str): If not None, this expression filters all of the
                ``expressions``.
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. If the function
                returns False or None, the ``TBranch`` is excluded; if the function
                returns True, it is included with its standard
                :ref:`uproot.behaviors.TBranch.TBranch.interpretation`; if an
                :doc:`uproot.interpretation.Interpretation`, this interpretation
                overrules the standard one.
            aliases (None or dict of str \u2192 str): Mathematical expressions that
                can be used in ``expressions`` or other aliases (without cycles).
                Uses the ``language`` engine to evaluate. If None, only the
                :ref:`uproot.behaviors.TBranch.TBranch.aliases` are available.
            language (:doc:`uproot.language.Language`): Language used to interpret
                the ``expressions`` and ``aliases``.
            entry_start (None or int): The first entry to include. If None, start
                at zero. If negative, count from the end, like a Python slice.
            entry_stop (None or int): The first entry to exclude (i.e. one greater
                than the last entry to include). If None, stop at
                :ref:`uproot.behaviors.TTree.TTree.num_entries`. If negative,
                count from the end, like a Python slice.
            step_size (int or str): If an integer, the maximum number of entries to
                include in each iteration step; if a string, the maximum memory size
                to include. The string must be a number followed by a memory unit,
                such as "100 MB".
            decompression_executor (None or Executor with a ``submit`` method): The
                executor that is used to decompress ``TBaskets``; if None, the
                file's :ref:`uproot.reading.ReadOnlyFile.decompression_executor`
                is used.
            interpretation_executor (None or Executor with a ``submit`` method): The
                executor that is used to interpret uncompressed ``TBasket`` data as
                arrays; if None, the file's :ref:`uproot.reading.ReadOnlyFile.interpretation_executor`
                is used.
            library (str or :doc:`uproot.interpretation.library.Library`): The library
                that is used to represent arrays. Options are ``"np"`` for NumPy,
                ``"ak"`` for Awkward Array, and ``"pd"`` for Pandas.
            how (None, str, or container type): Library-dependent instructions
                for grouping. The only recognized container types are ``tuple``,
                ``list``, and ``dict``. Note that the container *type itself*
                must be passed as ``how``, not an instance of that type (i.e.
                ``how=tuple``, not ``how=()``).
            report (bool): If True, this generator yields
                (arrays, :doc:`uproot.behaviors.TBranch.Report`) pairs; if False,
                it only yields arrays. The report has data about the ``TFile``,
                ``TTree``, and global and local entry ranges.

        Iterates through contiguous chunks of entries from the ``TTree``.

        For example:

        .. code-block:: python

            >>> for array in tree.iterate(["x", "y"], step_size=100):
            ...     # each of the following have 100 entries
            ...     array["x"], array["y"]

        See also :ref:`uproot.behaviors.TBranch.HasBranches.arrays` to read
        everything in a single step, without iteration.

        See also :doc:`uproot.behaviors.TBranch.iterate` to iterate over many
        files.
        """
        keys = _keys_deep(self)
        if isinstance(self, TBranch) and expressions is None and len(keys) == 0:
            filter_branch = uproot._util.regularize_filter(filter_branch)
            yield from self.parent.iterate(
                expressions=expressions,
                cut=cut,
                filter_name=filter_name,
                filter_typename=filter_typename,
                filter_branch=lambda branch: branch is self and filter_branch(branch),
                aliases=aliases,
                language=language,
                entry_start=entry_start,
                entry_stop=entry_stop,
                step_size=step_size,
                decompression_executor=decompression_executor,
                interpretation_executor=interpretation_executor,
                library=library,
                how=how,
                report=report,
            )

        else:
            entry_start, entry_stop = _regularize_entries_start_stop(
                self.tree.num_entries, entry_start, entry_stop
            )
            decompression_executor, interpretation_executor = _regularize_executors(
                decompression_executor, interpretation_executor, self._file
            )
            library = uproot.interpretation.library._regularize_library(library)

            aliases = _regularize_aliases(self, aliases)
            (
                arrays,
                expression_context,
                branchid_interpretation,
            ) = _regularize_expressions(
                self,
                expressions,
                cut,
                filter_name,
                filter_typename,
                filter_branch,
                keys,
                aliases,
                language,
                (lambda branchname, interpretation: None),
            )

            entry_step = _regularize_step_size(
                self, step_size, entry_start, entry_stop, branchid_interpretation
            )

            previous_baskets = {}
            for sub_entry_start in range(entry_start, entry_stop, entry_step):
                sub_entry_stop = min(sub_entry_start + entry_step, entry_stop)
                if sub_entry_stop - sub_entry_start == 0:
                    continue

                ranges_or_baskets = []
                checked = set()
                for _, context in expression_context:
                    for branch in context["branches"]:
                        if branch.cache_key not in checked:
                            checked.add(branch.cache_key)
                            for (
                                basket_num,
                                range_or_basket,
                            ) in branch.entries_to_ranges_or_baskets(
                                sub_entry_start, sub_entry_stop
                            ):
                                previous_basket = previous_baskets.get(
                                    (branch.cache_key, basket_num)
                                )
                                if previous_basket is None:
                                    ranges_or_baskets.append(
                                        (branch, basket_num, range_or_basket)
                                    )
                                else:
                                    ranges_or_baskets.append(
                                        (branch, basket_num, previous_basket)
                                    )

                arrays = {}
                _ranges_or_baskets_to_arrays(
                    self,
                    ranges_or_baskets,
                    branchid_interpretation,
                    sub_entry_start,
                    sub_entry_stop,
                    decompression_executor,
                    interpretation_executor,
                    library,
                    arrays,
                    True,
                )

                _fix_asgrouped(
                    arrays, expression_context, branchid_interpretation, library, how
                )

                output = language.compute_expressions(
                    self,
                    arrays,
                    expression_context,
                    keys,
                    aliases,
                    self.file.file_path,
                    self.object_path,
                )

                # no longer needed; save memory
                del arrays

                minimized_expression_context = [
                    (e, c)
                    for e, c in expression_context
                    if c["is_primary"] and not c["is_cut"]
                ]

                out = library.group(output, minimized_expression_context, how)

                next_baskets = {}
                for branch, basket_num, basket in ranges_or_baskets:
                    basket_entry_start, basket_entry_stop = basket.entry_start_stop
                    if basket_entry_stop > sub_entry_stop:
                        next_baskets[branch.cache_key, basket_num] = basket

                previous_baskets = next_baskets

                if report:
                    yield out, Report(self, sub_entry_start, sub_entry_stop)
                else:
                    yield out

    def keys(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
        full_paths=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only return the names of branches directly accessible
                under this object.
            full_paths (bool): If True, include the full path to each subbranch
                with slashes (``/``); otherwise, use the descendant's name as
                the output name.

        Returns the names of the subbranches as a list of strings.
        """
        return list(
            self.iterkeys(
                filter_name=filter_name,
                filter_typename=filter_typename,
                filter_branch=filter_branch,
                recursive=recursive,
                full_paths=full_paths,
            )
        )

    def values(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only return branches that are directly accessible
                under this object.

        Returns the subbranches as a list of
        :doc:`uproot.behaviors.TBranch.TBranch`.

        (Note: with ``recursive=False``, this is the same as
        :ref:`uproot.behaviors.TBranch.HasBranches.branches`.)
        """
        return list(
            self.itervalues(
                filter_name=filter_name,
                filter_typename=filter_typename,
                filter_branch=filter_branch,
                recursive=recursive,
            )
        )

    def items(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
        full_paths=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only return (name, branch) pairs for branches
                directly accessible under this object.
            full_paths (bool): If True, include the full path to each subbranch
                with slashes (``/``) in the name; otherwise, use the descendant's
                name as the name without modification.

        Returns (name, branch) pairs of the subbranches as a list of 2-tuples
        of (str, :doc:`uproot.behaviors.TBranch.TBranch`).
        """
        return list(
            self.iteritems(
                filter_name=filter_name,
                filter_typename=filter_typename,
                filter_branch=filter_branch,
                recursive=recursive,
                full_paths=full_paths,
            )
        )

    def typenames(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
        full_paths=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only return (name, typename) pairs for branches
                directly accessible under this object.
            full_paths (bool): If True, include the full path to each subbranch
                with slashes (``/``) in the name; otherwise, use the descendant's
                name as the name without modification.

        Returns (name, typename) pairs of the subbranches as a dict of
        str \u2192 str.
        """
        return dict(
            self.itertypenames(
                filter_name=filter_name,
                filter_typename=filter_typename,
                filter_branch=filter_branch,
                recursive=recursive,
                full_paths=full_paths,
            )
        )

    def iterkeys(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
        full_paths=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only return the names of branches directly accessible
                under this object.
            full_paths (bool): If True, include the full path to each subbranch
                with slashes (``/``); otherwise, use the descendant's name as
                the output name.

        Returns the names of the subbranches as an iterator over strings.
        """
        for k, _ in self.iteritems(
            filter_name=filter_name,
            filter_typename=filter_typename,
            filter_branch=filter_branch,
            recursive=recursive,
            full_paths=full_paths,
        ):
            yield k

    def itervalues(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only return branches that are directly accessible
                under this object.

        Returns the subbranches as an iterator over
        :doc:`uproot.behaviors.TBranch.TBranch`.

        (Note: with ``recursive=False``, this is the same as
        :ref:`uproot.behaviors.TBranch.HasBranches.branches`.)
        """
        for _, v in self.iteritems(
            filter_name=filter_name,
            filter_typename=filter_typename,
            filter_branch=filter_branch,
            recursive=recursive,
            full_paths=False,
        ):
            yield v

    def iteritems(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
        full_paths=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only return (name, branch) pairs for branches
                directly accessible under this object.
            full_paths (bool): If True, include the full path to each subbranch
                with slashes (``/``) in the name; otherwise, use the descendant's
                name as the name without modification.

        Returns (name, branch) pairs of the subbranches as an iterator over
        2-tuples of (str, :doc:`uproot.behaviors.TBranch.TBranch`).
        """
        filter_name = uproot._util.regularize_filter(filter_name)
        filter_typename = uproot._util.regularize_filter(filter_typename)
        if filter_branch is None:
            filter_branch = no_filter
        elif callable(filter_branch):
            pass
        else:
            raise TypeError(
                "filter_branch must be None or a function: TBranch -> bool, not {}".format(
                    repr(filter_branch)
                )
            )

        for branch in self.branches:
            if (
                (
                    filter_name is no_filter
                    or _filter_name_deep(filter_name, self, branch)
                )
                and (filter_typename is no_filter or filter_typename(branch.typename))
                and (filter_branch is no_filter or filter_branch(branch))
            ):
                yield branch.name, branch

            if recursive:
                for k1, v in branch.iteritems(
                    recursive=recursive,
                    filter_name=no_filter,
                    filter_typename=filter_typename,
                    filter_branch=filter_branch,
                    full_paths=full_paths,
                ):
                    if full_paths:
                        k2 = f"{branch.name}/{k1}"
                    else:
                        k2 = k1
                    if filter_name is no_filter or _filter_name_deep(
                        filter_name, self, v
                    ):
                        yield k2, v

    def itertypenames(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
        full_paths=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only return (name, typename) pairs for branches
                directly accessible under this object.
            full_paths (bool): If True, include the full path to each subbranch
                with slashes (``/``) in the name; otherwise, use the descendant's
                name as the name without modification.

        Returns (name, typename) pairs of the subbranches as an iterator over
        2-tuples of (str, str).
        """
        for k, v in self.iteritems(
            filter_name=filter_name,
            filter_typename=filter_typename,
            filter_branch=filter_branch,
            recursive=recursive,
            full_paths=full_paths,
        ):
            yield k, v.typename

    def _ipython_key_completions_(self):
        """
        Supports key-completion in an IPython or Jupyter kernel.
        """
        return self.iterkeys()

    def num_entries_for(
        self,
        memory_size,
        expressions=None,
        cut=None,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        aliases=None,
        language=uproot.language.python.python_language,
        entry_start=None,
        entry_stop=None,
    ):
        """
        Args:
            memory_size (int or str): An integer is interpreted as a number of
                bytes and a string must be a number followed by a unit, such as
                "100 MB".
            expressions (None, str, or list of str): Names of ``TBranches`` or
                aliases to convert to arrays or mathematical expressions of them.
                Uses the ``language`` to evaluate. If None, all ``TBranches``
                selected by the filters are included.
            cut (None or str): If not None, this expression filters all of the
                ``expressions``.
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            aliases (None or dict of str \u2192 str): Mathematical expressions that
                can be used in ``expressions`` or other aliases (without cycles).
                Uses the ``language`` engine to evaluate. If None, only the
                :ref:`uproot.behaviors.TBranch.TBranch.aliases` are available.
            language (:doc:`uproot.language.Language`): Language used to interpret
                the ``expressions`` and ``aliases``.
            entry_start (None or int): The first entry to include. If None, start
                at zero. If negative, count from the end, like a Python slice.
            entry_stop (None or int): The first entry to exclude (i.e. one greater
                than the last entry to include). If None, stop at
                :ref:`uproot.behaviors.TTree.TTree.num_entries`. If negative,
                count from the end, like a Python slice.

        Returns an *approximate* step size as a number of entries to read
        a given ``memory_size`` in each step.

        This method does not actually read the ``TBranch`` data or compute any
        expressions to arrive at its estimate. It only uses metadata from the
        already-loaded ``TTree``; it only needs ``language`` to parse the
        expressions, not to evaluate them.

        In addition, the estimate is based on compressed ``TBasket`` sizes
        (the amount of data that would have to be read), not uncompressed
        ``TBasket`` sizes (the amount of data that the final arrays would use
        in memory, without considering ``cuts``).

        This is the algorithm that
        :ref:`uproot.behaviors.TBranch.HasBranches.iterate` uses to convert a
        ``step_size`` expressed in memory units into a number of entries.
        """
        target_num_bytes = uproot._util.memory_size(memory_size)

        entry_start, entry_stop = _regularize_entries_start_stop(
            self.tree.num_entries, entry_start, entry_stop
        )

        keys = _keys_deep(self)
        aliases = _regularize_aliases(self, aliases)
        arrays, expression_context, branchid_interpretation = _regularize_expressions(
            self,
            expressions,
            cut,
            filter_name,
            filter_typename,
            filter_branch,
            keys,
            aliases,
            language,
            (lambda branchname, interpretation: None),
        )

        return _hasbranches_num_entries_for(
            self, target_num_bytes, entry_start, entry_stop, branchid_interpretation
        )

    def common_entry_offsets(
        self,
        filter_name=no_filter,
        filter_typename=no_filter,
        filter_branch=no_filter,
        recursive=True,
    ):
        """
        Args:
            filter_name (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by name.
            filter_typename (None, glob string, regex string in ``"/pattern/i"`` syntax, function of str \u2192 bool, or iterable of the above): A
                filter to select ``TBranches`` by type.
            filter_branch (None or function of :doc:`uproot.behaviors.TBranch.TBranch` \u2192 bool, :doc:`uproot.interpretation.Interpretation`, or None): A
                filter to select ``TBranches`` using the full
                :doc:`uproot.behaviors.TBranch.TBranch` object. The ``TBranch`` is
                included if the function returns True, excluded if it returns False.
            recursive (bool): If True, descend into any nested subbranches.
                If False, only consider branches directly accessible under this
                object. (Only applies when ``branches=None``.)

        Returns entry offsets in which ``TBasket`` boundaries align in the
        specified set of branches.

        If this :doc:`uproot.behaviors.TBranch.TBranch` has no subbranches,
        the output is identical to
        :ref:`uproot.behaviors.TBranch.TBranch.entry_offsets`.
        """
        common_offsets = None
        for branch in self.itervalues(
            filter_name=filter_name,
            filter_typename=filter_typename,
            filter_branch=filter_branch,
            recursive=recursive,
        ):
            if common_offsets is None:
                common_offsets = set(branch.entry_offsets)
            else:
                common_offsets = common_offsets.intersection(set(branch.entry_offsets))
        return sorted(common_offsets)

    def __getitem__(self, where):
        original_where = where

        got = self._lookup.get(original_where)
        if got is not None:
            return got

        if uproot._util.isint(where):
            return self.branches[where]
        elif uproot._util.isstr(where):
            where = uproot._util.ensure_str(where)
        else:
            raise TypeError(f"where must be an integer or a string, not {where!r}")

        if where.startswith("/"):
            recursive = False
            where = where[1:]
        else:
            recursive = True

        if "/" in where:
            where = "/".join([x for x in where.split("/") if x != ""])
            for k, v in self.iteritems(recursive=True, full_paths=True):
                if where == k:
                    self._lookup[original_where] = v
                    return v
            else:
                raise uproot.KeyInFileError(
                    original_where,
                    keys=self.keys(recursive=recursive),
                    file_path=self._file.file_path,
                    object_path=self.object_path,
                )

        elif recursive:
            got = _get_recursive(self, where)
            if got is not None:
                self._lookup[original_where] = got
                return got
            else:
                raise uproot.KeyInFileError(
                    original_where,
                    keys=self.keys(recursive=recursive),
                    file_path=self._file.file_path,
                    object_path=self.object_path,
                )

        else:
            for branch in self.branches:
                if branch.name == where:
                    self._lookup[original_where] = branch
                    return branch
            else:
                raise uproot.KeyInFileError(
                    original_where,
                    keys=self.keys(recursive=recursive),
                    file_path=self._file.file_path,
                    object_path=self.object_path,
                )

    def __iter__(self):
        yield from self.branches

    def __len__(self):
        return len(self.branches)


_branch_clean_name = re.compile(r"(.*\.)*([^\.\[\]]*)(\[.*\])*")
_branch_clean_parent_name = re.compile(r"(.*\.)*([^\.\[\]]*)\.([^\.\[\]]*)(\[.*\])*")


class TBranch(HasBranches):
    """
    Behaviors for a ``TBranch``, which mostly consist of array-reading methods.

    Since a :doc:`uproot.behaviors.TBranch.TBranch` is a
    :doc:`uproot.behaviors.TBranch.HasBranches`, it is also a Python
    ``Mapping``, which uses square bracket syntax to extract subbranches:

    .. code-block:: python

        my_branch["subbranch"]
        my_branch["subbranch"]["subsubbranch"]
        my_branch["subbranch/subsubbranch"]
    """

    def __repr__(self):
        if len(self) == 0:
            return "<{} {} at 0x{:012x}>".format(
                self.classname, repr(self.name), id(self)
            )
        else:
            return "<{} {} ({} subbranches) at 0x{:012x}>".format(
                self.classname, repr(self.name), len(self), id(self)
            )

    def array(
        self,
        interpretation=None,
        entry_start=None,
        entry_stop=None,
        decompression_executor=None,
        interpretation_executor=None,
        array_cache="inherit",
        library="ak",
    ):
        """
        Args:
            interpretation (None or :doc:`uproot.interpretation.Interpretation`): An
                interpretation of the ``TBranch`` data as an array. If None, the
                standard :ref:`uproot.behaviors.TBranch.TBranch.interpretation`
                is used, which is derived from
                :doc:`uproot.interpretation.identify.interpretation_of`.
            entry_start (None or int): The first entry to include. If None, start
                at zero. If negative, count from the end, like a Python slice.
            entry_stop (None or int): The first entry to exclude (i.e. one greater
                than the last entry to include). If None, stop at
                :ref:`uproot.behaviors.TTree.TTree.num_entries`. If negative,
                count from the end, like a Python slice.
            decompression_executor (None or Executor with a ``submit`` method): The
                executor that is used to decompress ``TBaskets``; if None, the
                file's :ref:`uproot.reading.ReadOnlyFile.decompression_executor`
                is used.
            interpretation_executor (None or Executor with a ``submit`` method): The
                executor that is used to interpret uncompressed ``TBasket`` data as
                arrays; if None, the file's :ref:`uproot.reading.ReadOnlyFile.interpretation_executor`
                is used.
            array_cache ("inherit", None, MutableMapping, or memory size): Cache of arrays;
                if "inherit", use the file's cache; if None, do not use a cache;
                if a memory size, create a new cache of this size.
            library (str or :doc:`uproot.interpretation.library.Library`): The library
                that is used to represent arrays. Options are ``"np"`` for NumPy,
                ``"ak"`` for Awkward Array, and ``"pd"`` for Pandas.

        Returns the ``TBranch`` data as an array.

        For example:

        .. code-block:: python

            >>> array = tree
            >>> array = tree.arrays(["x", "y"])    # only reads branches "x" and "y"
            >>> array
            <Array [{x: -41.2, y: 17.4}, ... {x: 32.5, y: 1.2}], type='2304 * {"x": float64,...'>
            >>> array["x"]
            <Array [-41.2, 35.1, 35.1, ... 32.4, 32.5] type='2304 * float64'>
            >>> array["y"]
            <Array [17.4, -16.6, -16.6, ... 1.2, 1.2, 1.2] type='2304 * float64'>

        See also :ref:`uproot.behaviors.TBranch.HasBranches.arrays` to read
        multiple ``TBranches`` into a group of arrays or an array-group.
        """
        if interpretation is None:
            interpretation = self.interpretation
        else:
            interpretation = _regularize_interpretation(interpretation)

        entry_start, entry_stop = _regularize_entries_start_stop(
            self.num_entries, entry_start, entry_stop
        )
        decompression_executor, interpretation_executor = _regularize_executors(
            decompression_executor, interpretation_executor, self._file
        )
        array_cache = _regularize_array_cache(array_cache, self._file)
        library = uproot.interpretation.library._regularize_library(library)

        def get_from_cache(branchname, interpretation):
            if array_cache is not None:
                cache_key = "{}:{}:{}:{}-{}:{}".format(
                    self.cache_key,
                    branchname,
                    interpretation.cache_key,
                    entry_start,
                    entry_stop,
                    library.name,
                )
                return array_cache.get(cache_key)
            else:
                return None

        arrays = {}
        expression_context = []
        branchid_interpretation = {}
        _regularize_branchname(
            self,
            self.name,
            self,
            interpretation,
            get_from_cache,
            arrays,
            expression_context,
            branchid_interpretation,
            True,
            False,
        )

        ranges_or_baskets = []
        checked = set()
        for _, context in expression_context:
            for branch in context["branches"]:
                if branch.cache_key not in checked:
                    checked.add(branch.cache_key)
                    for (
                        basket_num,
                        range_or_basket,
                    ) in branch.entries_to_ranges_or_baskets(entry_start, entry_stop):
                        ranges_or_baskets.append((branch, basket_num, range_or_basket))

        _ranges_or_baskets_to_arrays(
            self,
            ranges_or_baskets,
            branchid_interpretation,
            entry_start,
            entry_stop,
            decompression_executor,
            interpretation_executor,
            library,
            arrays,
            False,
        )

        _fix_asgrouped(
            arrays, expression_context, branchid_interpretation, library, None
        )

        if array_cache is not None:
            cache_key = "{}:{}:{}:{}-{}:{}".format(
                self.cache_key,
                self.name,
                interpretation.cache_key,
                entry_start,
                entry_stop,
                library.name,
            )
            array_cache[cache_key] = arrays[self.cache_key]

        return arrays[self.cache_key]

    def __array__(self, *args, **kwargs):
        out = self.array(library="np")
        if args == () and kwargs == {}:
            return out
        else:
            return numpy.array(out, *args, **kwargs)

    @property
    def name(self):
        """
        Name of the ``TBranch``.

        Note that ``TBranch`` names are not guaranteed to be unique; it is
        sometimes necessary to address a branch by its
        :ref:`uproot.behaviors.TBranch.TBranch.index`.
        """
        return self.member("fName")

    @property
    def title(self):
        """
        Title of the ``TBranch``.
        """
        return self.member("fTitle")

    @property
    def object_path(self):
        """
        Object path of the ``TBranch``.
        """
        if isinstance(self._parent, uproot.behaviors.TTree.TTree):
            sep = ":"
        else:
            sep = "/"
        return f"{self.parent.object_path}{sep}{self.name}"

    @property
    def cache_key(self):
        """
        String that uniquely specifies this ``TBranch`` in its path, to use as
        part of object and array cache keys.
        """
        if self._cache_key is None:
            if isinstance(self._parent, uproot.behaviors.TTree.TTree):
                sep = ":"
            else:
                sep = "/"
            self._cache_key = "{}{}{}({})".format(
                self.parent.cache_key, sep, self.name, self.index
            )
        return self._cache_key

    @property
    def index(self):
        """
        Integer position of this ``TBranch`` in its parent's list of branches.

        Useful for cases in which the
        :ref:`uproot.behaviors.TBranch.TBranch.name` is not unique: the
        non-recursive index is always unique.
        """
        for i, branch in enumerate(self.parent.branches):
            if branch is self:
                return i
        else:
            raise AssertionError

    @property
    def interpretation(self):
        """
        The standard :doc:`uproot.interpretation.Interpretation` of this
        ``TBranch`` as an array, derived from
        :doc:`uproot.interpretation.identify.interpretation_of`.

        If no interpretation could be found, the value of this property
        would be a :doc:`uproot.interpretation.identify.UnknownInterpretation`,
        which is a Python ``Exception``. Since the exception is *returned*,
        rather than *raised*, a branch lacking an interpretation is not a fatal
        error.

        However, any attempt to use this exception object as an
        :doc:`uproot.interpretation.Interpretation` causes it to raise itself:
        attempting to read a branch lacking an interpretation is a fatal error.
        """
        if self._interpretation is None:
            try:
                self._interpretation = uproot.interpretation.identify.interpretation_of(
                    self, {}
                )
            except uproot.interpretation.identify.UnknownInterpretation as err:
                self._interpretation = err
        return self._interpretation

    @property
    def typename(self):
        """
        The C++ typename of the ``TBranch``, derived from its
        :ref:`uproot.behaviors.TBranch.TBranch.interpretation`. If the
        interpretation is
        :doc:`uproot.interpretation.identify.UnknownInterpretation`, the
        typename is ``"unknown"``.
        """
        if self.interpretation is None:
            return "unknown"
        else:
            return self.interpretation.typename

    @property
    def num_entries(self):
        """
        The number of entries in the ``TBranch``, as reported by ``fEntries``.

        In principle, this could disagree with the
        :ref:`uproot.behaviors.TTree.TTree.num_entries`, which is from the
        ``TTree``'s ``fEntries``.

        The ``TBranch`` also has a ``fEntryNumber``, which ought to be equal to
        the ``TBranch`` and ``TTree``'s ``fEntries``, and the last value of
        :ref:`uproot.behaviors.TBranch.TBranch.entry_offsets` ought to be
        equal to the number of entries as well.
        """
        return int(self.member("fEntries"))  # or fEntryNumber?

    @property
    def entry_offsets(self):
        """
        The starting and stopping entry numbers for all the ``TBaskets`` in the
        ``TBranch`` as a list of increasing, non-negative integers.

        The number of ``entry_offsets`` in this list of integers is one more
        than the number of ``TBaskets``. The first is ``0`` and the last is
        the number of entries
        (:ref:`uproot.behaviors.TBranch.TBranch.num_entries`).
        """
        if self._num_normal_baskets == 0:
            out = [0]
        else:
            out = self.member("fBasketEntry")[: self._num_normal_baskets + 1].tolist()
        num_entries_normal = out[-1]

        for basket in self.embedded_baskets:
            out.append(out[-1] + basket.num_entries)

        if (
            out[-1] != self.num_entries
            and self.interpretation is not None
            and not isinstance(
                self.interpretation, uproot.interpretation.grouped.AsGrouped
            )
        ):
            raise ValueError(
                """entries in normal baskets ({}) plus embedded baskets ({}) """
                """don't add up to expected number of entries ({})
in file {}""".format(
                    num_entries_normal,
                    sum(basket.num_entries for basket in self.embedded_baskets),
                    self.num_entries,
                    self._file.file_path,
                )
            )
        else:
            return out

    def basket_entry_start_stop(self, basket_num):
        """
        The starting and stopping entry number for ``TBasket`` number ``basket_num``.
        """
        if 0 <= basket_num < self._num_normal_baskets:
            fBasketEntry = self.member("fBasketEntry")
            return fBasketEntry[basket_num], fBasketEntry[basket_num + 1]

        elif 0 <= basket_num < self.num_baskets:
            baskets_before = self._num_normal_baskets
            if self._num_normal_baskets == 0:
                entries_before = 0
            else:
                entries_before = self.member("fBasketEntry")[self._num_normal_baskets]

            for basket in self.embedded_baskets:
                if basket_num == baskets_before:
                    return entries_before, entries_before + basket.num_entries
                baskets_before += 1
                entries_before += basket.num_entries
            else:
                raise AssertionError

        else:
            raise IndexError(
                """branch {} has {} baskets; cannot get starting entry """
                """for basket {}
in file {}""".format(
                    repr(self.name), self.num_baskets, basket_num, self._file.file_path
                )
            )

    @property
    def tree(self):
        """
        The ``TTree`` to which this ``TBranch`` belongs. The branch might be
        deeply nested; this property ascends all the way to the top.
        """
        out = self
        while not isinstance(out, uproot.behaviors.TTree.TTree):
            out = out.parent
        return out

    @property
    def top_level(self):
        """
        True if this branch's immediate :ref:`uproot.model.Model.parent`
        is the ``TTree``; False otherwise.
        """
        return isinstance(self.parent, uproot.behaviors.TTree.TTree)

    @property
    def streamer(self):
        """
        The ``TStreamerInfo`` or ``TStreamerElement`` for this ``TBranch``,
        which may be None.

        If the :ref:`uproot.reading.ReadOnlyFile.streamers` have not yet been
        read, this method *might* cause them to be read. (Only
        ``TBranchElements`` can have streamers.)
        """
        if self._streamer is None:
            clean_name = _branch_clean_name.match(self.name).group(2)
            clean_parentname = _branch_clean_parent_name.match(self.name)
            fParentName = self.member("fParentName", none_if_missing=True)
            fClassName = self.member("fClassName", none_if_missing=True)

            if fParentName is not None and fParentName != "":
                matches = self._file.streamers.get(fParentName)

                if matches is not None:
                    streamerinfo = matches[max(matches)]

                    for element in streamerinfo.walk_members(self._file.streamers):
                        if element.name == clean_name and (
                            fClassName is None
                            or fClassName == ""
                            or element.parent is None
                            or element.parent.name == ""
                            or element.parent.name == fClassName
                        ):
                            self._streamer = element
                            break

                    if self._streamer is None and clean_parentname is not None:
                        clean_parentname = clean_parentname.group(2)
                        for element in streamerinfo.walk_members(self._file.streamers):
                            if element.name == clean_parentname:
                                substreamerinfo = self._file.streamer_named(
                                    element.typename
                                )
                                for subelement in substreamerinfo.walk_members(
                                    self._file.streamers
                                ):
                                    if subelement.name == clean_name:
                                        self._streamer = subelement
                                        break
                                break

                    if (
                        self.parent.member("fClassName") == "TClonesArray"
                        or self.parent.member("fClonesName", none_if_missing=True)
                        == fParentName
                    ):
                        self._streamer_isTClonesArray = True

            elif fClassName is not None and fClassName != "":
                if fClassName == "TClonesArray":
                    self._streamer_isTClonesArray = True
                    matches = self._file.streamers.get(
                        self.member("fClonesName", none_if_missing=True)
                    )
                else:
                    matches = self._file.streamers.get(fClassName)

                if matches is not None:
                    self._streamer = matches[max(matches)]

        return self._streamer

    @property
    def context(self):
        """
        Auxiliary data used in deserialization. This is a *copy* of the
        ``context`` dict at the time that the ``TBranch`` was deserialized
        with ``"in_TBranch": True`` added.
        """
        return self._context

    @property
    def aliases(self):
        """
        The :ref:`uproot.behaviors.TTree.TTree.aliases`, which are used as the
        ``aliases`` argument to
        :ref:`uproot.behaviors.TBranch.HasBranches.arrays`,
        :ref:`uproot.behaviors.TBranch.HasBranches.iterate`,
        :doc:`uproot.behaviors.TBranch.iterate`, and
        :doc:`uproot.behaviors.TBranch.concatenate` if one is not given.

        The return type is always a dict of str \u2192 str, even if there
        are no aliases (an empty dict).
        """
        return self.tree.aliases

    @property
    def count_branch(self):
        """
        The ``TBranch`` object in which this branch's "counts" reside or None
        if this branch has no "counts".
        """
        out = self.count_leaf
        while isinstance(out, uproot.model.Model) and out.is_instance("TLeaf"):
            out = out.parent
        if isinstance(out, uproot.model.Model) and out.is_instance("TBranch"):
            return out
        else:
            return None

    @property
    def count_leaf(self):
        """
        The ``TLeaf`` object of this branch's "counts" or None if this branch
        has no "counts".
        """
        leaves = self.member("fLeaves")
        if len(leaves) != 1:
            return None
        return leaves[0].member("fLeafCount")

    @property
    def compression(self):
        """
        A :doc:`uproot.compression.Compression` object describing the
        compression setting for the ``TBranch``.

        Note that different ``TBranches`` in a ``TTree`` can be compressed
        differently from each other, and they can be compressed differently
        from the file's global compression setting.

        It is also *in principle possible* for the blocks in each ``TBasket``
        to be compresssed differently: see
        :ref:`uproot.models.TBasket.Model_TBasket.block_compression_info` if
        you're paranoid.
        """
        return uproot.compression.Compression.from_code(self.member("fCompress"))

    @property
    def compressed_bytes(self):
        """
        The number of compressed bytes in all ``TBaskets`` of this ``TBranch``,
        including the TKey headers (which are always uncompressed).

        This information is specified in the ``TBranch`` metadata (``fZipBytes``)
        and can be determined without reading any additional data.
        """
        return self.member("fZipBytes")

    @property
    def uncompressed_bytes(self):
        """
        The number of uncompressed bytes in all ``TBaskets`` of this ``TBranch``,
        including the TKey headers.

        This information is specified in the ``TBranch`` metadata (``fTotBytes``)
        and can be determined without reading any additional data.
        """
        return self.member("fTotBytes")

    @property
    def compression_ratio(self):
        """
        The number of uncompressed bytes divided by the number of compressed
        bytes for this ``TBranch``.

        See :ref:`uproot.behaviors.TBranch.TBranch.compressed_bytes` and
        :ref:`uproot.behaviors.TBranch.TBranch.uncompressed_bytes`.
        """
        return float(self.uncompressed_bytes) / float(self.compressed_bytes)

    @property
    def num_baskets(self):
        """
        The number of ``TBaskets`` in this ``TBranch``, including both normal
        (free) ``TBaskets`` and
        :ref:`uproot.behaviors.TBranch.TBranch.embedded_baskets`.
        """
        return self._num_normal_baskets + len(self.embedded_baskets)

    def basket(self, basket_num):
        """
        The :doc:`uproot.models.TBasket.Model_TBasket` at index ``basket_num``.

        It may be a normal (free) ``TBasket`` or one of the
        :ref:`uproot.behaviors.TBranch.TBranch.embedded_baskets`.
        """
        if 0 <= basket_num < self._num_normal_baskets:
            chunk, cursor = self.basket_chunk_cursor(basket_num)
            return uproot.models.TBasket.Model_TBasket.read(
                chunk, cursor, {"basket_num": basket_num}, self._file, self._file, self
            )
        elif 0 <= basket_num < self.num_baskets:
            return self.embedded_baskets[basket_num - self._num_normal_baskets]
        else:
            raise IndexError(
                """branch {} has {} baskets; cannot get basket {}
in file {}""".format(
                    repr(self.name), self.num_baskets, basket_num, self._file.file_path
                )
            )

    def basket_chunk_cursor(self, basket_num):
        """
        Returns a :doc:`uproot.source.chunk.Chunk` and
        :doc:`uproot.source.cursor.Cursor` as a 2-tuple for a given
        ``basket_num``.

        If the file source is :doc:`uproot.source.file.MemmapSource`
        and the file gets closed, accessing the Chunk would cause
        a segfault. If that's a possibility, be sure to call
        :doc:`uproot.source.chunk.Chunk.detach_memmap` to ensure
        that any memmap-derived data gets copied for safety.
        """
        if 0 <= basket_num < self._num_normal_baskets:
            start = self.member("fBasketSeek")[basket_num]
            stop = start + self.basket_compressed_bytes(basket_num)
            cursor = uproot.source.cursor.Cursor(start)
            chunk = self._file.source.chunk(start, stop)
            return chunk, cursor
        elif 0 <= basket_num < self.num_baskets:
            raise IndexError(
                """branch {} has {} normal baskets; cannot get chunk and """
                """cursor for basket {} because only normal baskets have cursors
in file {}""".format(
                    repr(self.name),
                    self._num_normal_baskets,
                    basket_num,
                    self._file.file_path,
                )
            )
        else:
            raise IndexError(
                """branch {} has {} baskets; cannot get cursor and chunk """
                """for basket {}
in file {}""".format(
                    repr(self.name), self.num_baskets, basket_num, self._file.file_path
                )
            )

    def basket_compressed_bytes(self, basket_num):
        """
        The number of compressed bytes for the ``TBasket`` at ``basket_num``,
        including the TKey header.

        The number of compressed bytes is specified in the ``TBranch`` metadata
        and can be determined without reading any additional data. The
        uncompressed bytes requires reading the ``TBasket``'s ``TKey`` at least.
        """
        if 0 <= basket_num < self._num_normal_baskets:
            return int(self.member("fBasketBytes")[basket_num])
        elif 0 <= basket_num < self.num_baskets:
            return self.embedded_baskets[
                basket_num - self._num_normal_baskets
            ].compressed_bytes
        else:
            raise IndexError(
                """branch {} has {} baskets; cannot get basket chunk {}
in file {}""".format(
                    repr(self.name), self.num_baskets, basket_num, self._file.file_path
                )
            )

    def basket_uncompressed_bytes(self, basket_num):
        """
        The number of uncompressed bytes for the ``TBasket`` at ``basket_num``,
        including the TKey header.

        The number of uncompressed bytes cannot be determined without reading a
        ``TKey``, which are small, but may be slow for remote connections because
        of the latency of round-trip requests.
        """
        if 0 <= basket_num < self.num_baskets:
            return self.basket(basket_num).uncompressed_bytes
        else:
            return self.basket_key(basket_num).data_uncompressed_bytes

    def basket_key(self, basket_num):
        """
        The ``TKey`` (:doc:`uproot.reading.ReadOnlyKey`) for the ``TBasket``
        at ``basket_num``.

        Only applies to normal (free) ``TBaskets``, not
        :ref:`uproot.behaviors.TBranch.TBranch.embedded_baskets`.
        """
        if 0 <= basket_num < self._num_normal_baskets:
            start = self.member("fBasketSeek")[basket_num]
            stop = start + uproot.reading._key_format_big.size
            cursor = uproot.source.cursor.Cursor(start)

            # Chunk will not be retained; we don't have to detach_memmap()
            chunk = self._file.source.chunk(start, stop)

            return uproot.reading.ReadOnlyKey(
                chunk, cursor, {}, self._file, self, read_strings=False
            )

        elif 0 <= basket_num < self.num_baskets:
            raise ValueError(
                "branch {} basket {} is an embedded basket, which has no TKey".format(
                    repr(self.name), basket_num
                )
            )

        else:
            raise IndexError(
                """branch {} has {} baskets; cannot get basket chunk {}
in file {}""".format(
                    repr(self.name), self.num_baskets, basket_num, self._file.file_path
                )
            )

    @property
    def embedded_baskets(self):
        """
        The ``TBaskets`` that are embedded within the ``TBranch`` metadata,
        usually because the ROOT process that was writing the file closed
        unexpectedly.
        """
        if self._embedded_baskets is None:
            cursor = self._cursor_baskets.copy()
            baskets = uproot.models.TObjArray.Model_TObjArrayOfTBaskets.read(
                self.tree.chunk, cursor, {}, self._file, self._file, self
            )
            with self._embedded_baskets_lock:
                self._embedded_baskets = []
                for basket in baskets:
                    if basket is not None:
                        basket._basket_num = self._num_normal_baskets + len(
                            self._embedded_baskets
                        )
                        self._embedded_baskets.append(basket)

        return self._embedded_baskets

    def entries_to_ranges_or_baskets(self, entry_start, entry_stop):
        """
        Returns a list of (start, stop) integer pairs for free (normal)
        ``TBaskets`` and :doc:`uproot.models.TBasket.Model_TBasket` objects
        for embedded ``TBaskets``.

        The intention is for this list to be updated in place, replacing
        (start, stop) integer pairs with
        :doc:`uproot.models.TBasket.Model_TBasket` objects as they get
        read and interpreted.
        """
        entry_offsets = self.entry_offsets
        out = []
        start = entry_offsets[0]
        for basket_num, stop in enumerate(entry_offsets[1:]):
            if entry_start < stop and start <= entry_stop:
                if 0 <= basket_num < self._num_normal_baskets:
                    byte_start = self.member("fBasketSeek")[basket_num]
                    byte_stop = byte_start + self.basket_compressed_bytes(basket_num)
                    out.append((basket_num, (byte_start, byte_stop)))
                elif 0 <= basket_num < self.num_baskets:
                    out.append((basket_num, self.basket(basket_num)))
                else:
                    raise AssertionError((self.name, basket_num))
            start = stop
        return out

    def postprocess(self, chunk, cursor, context, file):
        fWriteBasket = self.member("fWriteBasket")

        self._lookup = {}
        self._interpretation = None
        self._typename = None
        self._streamer = None
        self._streamer_isTClonesArray = False
        self._cache_key = None
        self._context = dict(context)
        self._context["breadcrumbs"] = ()
        self._context["in_TBranch"] = True

        self._num_normal_baskets = 0
        for i, x in enumerate(self.member("fBasketSeek")):
            if x == 0 or i == fWriteBasket:
                break
            self._num_normal_baskets += 1

        # the number of entries in basket i == fBasketEntry[i + 1] - fBasketEntry[i]
        # but it's possible for len(fBasketEntry) == i (ROOT can read such files)
        # so in that rare case, look at the header of the last basket
        # and use that to extend the fBasketEntry array by one
        fBasketEntry = self.member("fBasketEntry")
        if len(fBasketEntry) == self._num_normal_baskets:
            start = self.member("fBasketSeek")[len(fBasketEntry) - 1]
            stop = start + self.basket_compressed_bytes(len(fBasketEntry) - 1)
            cursor = uproot.source.cursor.Cursor(start)
            chunk = self._file.source.chunk(start, stop)
            basket_header = uproot.models.TBasket.Model_TBasket.read(
                chunk, cursor, {"read_basket": False}, self._file, self._file, self
            )
            fBasketEntry = self._members["fBasketEntry"] = numpy.append(
                fBasketEntry, fBasketEntry[-1] + basket_header.member("fNevBuf")
            )

        if self.member("fEntries") == fBasketEntry[self._num_normal_baskets]:
            self._embedded_baskets = []
            self._embedded_baskets_lock = None

        elif self.has_member("fBaskets"):
            self._embedded_baskets = []
            for basket in self.member("fBaskets"):
                if basket is not None:
                    basket._basket_num = self._num_normal_baskets + len(
                        self._embedded_baskets
                    )
                    self._embedded_baskets.append(basket)
            self._embedded_baskets_lock = None

        else:
            self._embedded_baskets = None
            self._embedded_baskets_lock = threading.Lock()

        if "fIOFeatures" in self._parent.members:
            self._tree_iofeatures = self._parent.member("fIOFeatures").member("fIOBits")

        return self

    def debug(
        self,
        entry,
        skip_bytes=None,
        limit_bytes=None,
        dtype=None,
        offset=0,
        stream=sys.stdout,
    ):
        """
        Args:
            entry (int): Entry number to inspect. Note: this debugging routine
                is not applicable to data without entry offsets (nor would it
                be needed).
            skip_bytes (int): Number of bytes to skip before presenting the
                remainder of the ``entry``. May be negative, to examine the
                byte stream before the ``entry``.
            limit_bytes (None or int): Number of bytes to limit the output to.
                A line of debugging output (without any ``offset``) is 20 bytes,
                so multiples of 20 show full lines. If None, everything is
                shown to the end of the ``entry``, which might be large.
            dtype (None, ``numpy.dtype``, or its constructor argument): If None,
                present only the bytes as decimal values (0-255). Otherwise,
                also interpret them as an array of a given NumPy type.
            offset (int): Number of bytes to skip before interpreting a ``dtype``;
                can be helpful if the numerical values are out of phase with
                the first byte shown. Not to be confused with ``skip_bytes``,
                which determines which bytes are shown at all. Any ``offset``
                values that are equivalent modulo ``dtype.itemsize`` show
                equivalent interpretations.
            stream (object with a ``write(str)`` method): Stream to write the
                debugging output to.

        Presents the data for one entry as raw bytes.

        Example output with ``dtype=">f4"`` and ``offset=3``.

        .. code-block::

            --+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+-
            123 123 123  63 140 204 205  64  12 204 205  64  83  51  51  64 140 204 205  64
              {   {   {   ? --- --- ---   @ --- --- ---   @   S   3   3   @ --- --- ---   @
                                    1.1             2.2             3.3             4.4
                --+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+-
                176   0   0  64 211  51  51  64 246 102 102  65  12 204 205  65  30 102 102  66
                --- --- ---   @ ---   3   3   @ ---   f   f   A --- --- ---   A ---   f   f   B
                        5.5             6.6             7.7             8.8             9.9
                --+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+-
                202   0   0  67  74   0   0  67 151 128   0 123 123
                --- --- ---   C   J --- ---   C --- --- ---   {   {
                      101.0           202.0           303.0
        """
        data = self.debug_array(entry)
        chunk = uproot.source.chunk.Chunk.wrap(self._file.source, data)
        if skip_bytes is None:
            cursor = uproot.source.cursor.Cursor(0)
        else:
            cursor = uproot.source.cursor.Cursor(skip_bytes)
        cursor.debug(
            chunk, limit_bytes=limit_bytes, dtype=dtype, offset=offset, stream=stream
        )

    def debug_array(self, entry, skip_bytes=0, dtype=np_uint8):
        """
        Args:
            entry (int): Entry number to inspect. Note: this debugging routine
                is not applicable to data without entry offsets (nor would it
                be needed).
            skip_bytes (int): Number of bytes to skip before presenting the
                remainder of the ``entry``. May be negative, to examine the
                byte stream before the ``entry``.
            dtype (``numpy.dtype`` or its constructor argument): Data type in
                which to interpret the data. (The size of the array returned is
                truncated to this ``dtype.itemsize``.)

        Like :ref:`uproot.behaviors.TBranch.TBranch.debug`, but returns a
        NumPy array for further inspection.
        """
        dtype = numpy.dtype(dtype)
        interpretation = uproot.interpretation.jagged.AsJagged(
            uproot.interpretation.numerical.AsDtype("u1")
        )
        out = self.array(
            interpretation, entry_start=entry, entry_stop=entry + 1, library="np"
        )[0][skip_bytes:]
        return out[: (len(out) // dtype.itemsize) * dtype.itemsize].view(dtype)


def _filter_name_deep(filter_name, hasbranches, branch):
    shallow = name = branch.name
    if filter_name(name):
        return True
    while branch is not hasbranches:
        branch = branch.parent
        if branch is not hasbranches:
            name = branch.name + "/" + name
    if name != shallow and filter_name(name):
        return True
    return filter_name("/" + name)


def _keys_deep(hasbranches):
    out = set()
    for branch in hasbranches.itervalues(recursive=True):
        name = branch.name
        out.add(name)
        while branch is not hasbranches:
            branch = branch.parent
            if branch is not hasbranches:
                name = branch.name + "/" + name
        out.add(name)
        out.add("/" + name)
    return out


def _get_recursive(hasbranches, where):
    for branch in hasbranches.branches:
        if branch.name == where:
            return branch
        got = _get_recursive(branch, where)
        if got is not None:
            return got
    else:
        return None


def _regularize_entries_start_stop(num_entries, entry_start, entry_stop):
    if entry_start is None:
        entry_start = 0
    elif entry_start < 0:
        entry_start += num_entries
    entry_start = min(num_entries, max(0, entry_start))

    if entry_stop is None:
        entry_stop = num_entries
    elif entry_stop < 0:
        entry_stop += num_entries
    entry_stop = min(num_entries, max(0, entry_stop))

    if entry_stop < entry_start:
        entry_stop = entry_start

    return int(entry_start), int(entry_stop)


def _regularize_executors(decompression_executor, interpretation_executor, file):
    if file is None:
        if decompression_executor is None:
            decompression_executor = uproot.source.futures.TrivialExecutor()
        if interpretation_executor is None:
            interpretation_executor = uproot.source.futures.TrivialExecutor()
    else:
        if decompression_executor is None:
            decompression_executor = file.decompression_executor
        if interpretation_executor is None:
            interpretation_executor = file.interpretation_executor
    return decompression_executor, interpretation_executor


def _regularize_array_cache(array_cache, file):
    if isinstance(array_cache, MutableMapping):
        return array_cache
    elif uproot._util.isstr(array_cache) and array_cache == "inherit":
        return file._array_cache
    elif array_cache is None:
        return None
    elif uproot._util.isint(array_cache) or uproot._util.isstr(array_cache):
        return uproot.cache.LRUArrayCache(array_cache)
    else:
        raise TypeError("array_cache must be None, a MutableMapping, or a memory size")


def _regularize_aliases(hasbranches, aliases):
    if aliases is None:
        return hasbranches.aliases
    else:
        new_aliases = dict(hasbranches.aliases)
        new_aliases.update(aliases)
        return new_aliases


def _regularize_interpretation(interpretation):
    if isinstance(interpretation, uproot.interpretation.Interpretation):
        return interpretation
    elif isinstance(interpretation, numpy.dtype):
        return uproot.interpretation.numerical.AsDtype(interpretation)
    else:
        dtype = numpy.dtype(interpretation)
        dtype = dtype.newbyteorder(">")
        return uproot.interpretation.numerical.AsDtype(interpretation)


def _regularize_branchname(
    hasbranches,
    branchname,
    branch,
    interpretation,
    get_from_cache,
    arrays,
    expression_context,
    branchid_interpretation,
    is_primary,
    is_cut,
):
    got = get_from_cache(branchname, interpretation)
    if got is not None:
        arrays[branch.cache_key] = got

    is_jagged = isinstance(interpretation, uproot.interpretation.jagged.AsJagged)

    if isinstance(interpretation, uproot.interpretation.grouped.AsGrouped):
        branches = []
        for subname, subinterp in interpretation.subbranches.items():
            _regularize_branchname(
                hasbranches,
                subname,
                branch[subname],
                subinterp,
                get_from_cache,
                arrays,
                expression_context,
                branchid_interpretation,
                False,
                is_cut,
            )
            branches.extend(expression_context[-1][1]["branches"])

        branches.append(branch)
        arrays[branch.cache_key] = None

    else:
        branches = [branch]

    if branch.cache_key in branchid_interpretation:
        if (
            branchid_interpretation[branch.cache_key].cache_key
            != interpretation.cache_key
        ):
            raise ValueError(
                "a branch cannot be loaded with multiple interpretations: "
                "{} and {}".format(
                    repr(branchid_interpretation[branch.cache_key]),
                    repr(interpretation),
                )
            )
    else:
        branchid_interpretation[branch.cache_key] = interpretation

    c = {
        "is_primary": is_primary,
        "is_cut": is_cut,
        "is_jagged": is_jagged,
        "is_branch": True,
        "branches": branches,
    }
    expression_context.append((branchname, c))


def _regularize_expression(
    hasbranches,
    expression,
    keys,
    aliases,
    language,
    get_from_cache,
    arrays,
    expression_context,
    branchid_interpretation,
    symbol_path,
    is_cut,
    rename,
):
    is_primary = symbol_path == ()

    branch = hasbranches.get(expression)
    if branch is not None:
        _regularize_branchname(
            hasbranches,
            expression,
            branch,
            branch.interpretation,
            get_from_cache,
            arrays,
            expression_context,
            branchid_interpretation,
            is_primary,
            is_cut,
        )

    else:
        if expression in aliases:
            to_compute = aliases[expression]
        else:
            to_compute = expression

        is_jagged = False
        expression_branches = []
        for symbol in language.free_symbols(
            to_compute,
            keys,
            aliases,
            hasbranches.file.file_path,
            hasbranches.object_path,
        ):
            if symbol in symbol_path:
                raise ValueError(
                    """symbol {} is recursively defined with aliases:

    {}

in file {} at {}""".format(
                        repr(symbol),
                        "\n    ".join(f"{k}: {v}" for k, v in aliases.items()),
                        hasbranches.file.file_path,
                        hasbranches.object_path,
                    )
                )

            _regularize_expression(
                hasbranches,
                symbol,
                keys,
                aliases,
                language,
                get_from_cache,
                arrays,
                expression_context,
                branchid_interpretation,
                symbol_path + (symbol,),
                False,
                None,
            )
            if expression_context[-1][1]["is_jagged"]:
                is_jagged = True
            expression_branches.extend(expression_context[-1][1]["branches"])

        c = {
            "is_primary": is_primary,
            "is_cut": is_cut,
            "is_jagged": is_jagged,
            "is_branch": False,
            "branches": expression_branches,
        }
        if rename is not None:
            c["rename"] = rename
        expression_context.append((expression, c))


def _regularize_expressions(
    hasbranches,
    expressions,
    cut,
    filter_name,
    filter_typename,
    filter_branch,
    keys,
    aliases,
    language,
    get_from_cache,
):
    arrays = {}
    expression_context = []
    branchid_interpretation = {}

    if expressions is None:
        for branchname, branch in hasbranches.iteritems(
            filter_name=filter_name,
            filter_typename=filter_typename,
            filter_branch=filter_branch,
            recursive=True,
            full_paths=False,
        ):
            if not isinstance(
                branch.interpretation,
                (
                    uproot.interpretation.identify.UnknownInterpretation,
                    uproot.interpretation.grouped.AsGrouped,
                ),
            ):
                _regularize_expression(
                    hasbranches,
                    language.getter_of(branchname),
                    keys,
                    aliases,
                    language,
                    get_from_cache,
                    arrays,
                    expression_context,
                    branchid_interpretation,
                    (),
                    False,
                    branchname,
                )

    elif uproot._util.isstr(expressions):
        _regularize_expression(
            hasbranches,
            expressions,
            keys,
            aliases,
            language,
            get_from_cache,
            arrays,
            expression_context,
            branchid_interpretation,
            (),
            False,
            None,
        )

    elif isinstance(expressions, Iterable):
        if isinstance(expressions, dict):
            items = expressions.items()
        else:
            items = []
            for expression in expressions:
                if uproot._util.isstr(expression):
                    items.append((expression, None))
                elif isinstance(expression, tuple) and len(expression) == 2:
                    items.append(expression)
                else:
                    raise TypeError(
                        "iterable of expressions must be strings or "
                        "name, Interpretation pairs (length-2 tuples), not "
                        + repr(expression)
                    )

        for expression, interp in items:
            if interp is None:
                _regularize_expression(
                    hasbranches,
                    expression,
                    keys,
                    aliases,
                    language,
                    get_from_cache,
                    arrays,
                    expression_context,
                    branchid_interpretation,
                    (),
                    False,
                    None,
                )
            else:
                branch = hasbranches[expression]
                interp = _regularize_interpretation(interp)
                _regularize_branchname(
                    hasbranches,
                    expression,
                    branch,
                    interp,
                    get_from_cache,
                    arrays,
                    expression_context,
                    branchid_interpretation,
                    True,
                    False,
                )

    else:
        raise TypeError(
            "expressions must be None (for all branches), a string (single "
            "branch or expression), a list of strings (multiple), or a dict "
            "or list of name, Interpretation pairs (branch names and their "
            "new Interpretation), not {}".format(repr(expressions))
        )

    if cut is None:
        pass
    elif uproot._util.isstr(cut):
        _regularize_expression(
            hasbranches,
            cut,
            keys,
            aliases,
            language,
            get_from_cache,
            arrays,
            expression_context,
            branchid_interpretation,
            (),
            True,
            None,
        )

    return arrays, expression_context, branchid_interpretation


def _ranges_or_baskets_to_arrays(
    hasbranches,
    ranges_or_baskets,
    branchid_interpretation,
    entry_start,
    entry_stop,
    decompression_executor,
    interpretation_executor,
    library,
    arrays,
    update_ranges_or_baskets,
):
    notifications = queue.Queue()

    branchid_arrays = {}
    branchid_num_baskets = {}
    ranges = []
    range_args = {}
    range_original_index = {}
    original_index = 0

    for cache_key in branchid_interpretation:
        branchid_num_baskets[cache_key] = 0

    for branch, basket_num, range_or_basket in ranges_or_baskets:
        branchid_num_baskets[branch.cache_key] += 1

        if branch.cache_key not in branchid_arrays:
            branchid_arrays[branch.cache_key] = {}

        if isinstance(range_or_basket, tuple) and len(range_or_basket) == 2:
            range_or_basket = (int(range_or_basket[0]), int(range_or_basket[1]))
            ranges.append(range_or_basket)
            range_args[range_or_basket] = (branch, basket_num)
            range_original_index[range_or_basket] = original_index
        else:
            notifications.put(range_or_basket)

        original_index += 1

    for cache_key, interpretation in branchid_interpretation.items():
        if branchid_num_baskets[cache_key] == 0:
            if cache_key not in arrays:
                arrays[cache_key] = interpretation.final_array(
                    {}, 0, 0, [0], library, None
                )

    hasbranches._file.source.chunks(ranges, notifications=notifications)

    def replace(ranges_or_baskets, original_index, basket):
        branch, basket_num, range_or_basket = ranges_or_baskets[original_index]
        ranges_or_baskets[original_index] = branch, basket_num, basket

    def chunk_to_basket(chunk, branch, basket_num):
        try:
            cursor = uproot.source.cursor.Cursor(chunk.start)
            basket = uproot.models.TBasket.Model_TBasket.read(
                chunk,
                cursor,
                {"basket_num": basket_num},
                hasbranches._file,
                hasbranches._file,
                branch,
            )
            original_index = range_original_index[(chunk.start, chunk.stop)]
            if update_ranges_or_baskets:
                replace(ranges_or_baskets, original_index, basket)
        except Exception:
            notifications.put(sys.exc_info())
        else:
            notifications.put(basket)

    def basket_to_array(basket):
        try:
            assert basket.basket_num is not None
            branch = basket.parent
            interpretation = branchid_interpretation[branch.cache_key]
            basket_arrays = branchid_arrays[branch.cache_key]

            basket_arrays[basket.basket_num] = interpretation.basket_array(
                basket.data,
                basket.byte_offsets,
                basket,
                branch,
                branch.context,
                basket.member("fKeylen"),
                library,
            )
            if basket.num_entries != len(basket_arrays[basket.basket_num]):
                raise ValueError(
                    """basket {} in tree/branch {} has the wrong number of entries """
                    """(expected {}, obtained {}) when interpreted as {}
    in file {}""".format(
                        basket.basket_num,
                        branch.object_path,
                        basket.num_entries,
                        len(basket_arrays[basket.basket_num]),
                        interpretation,
                        branch.file.file_path,
                    )
                )

            basket = None

            if len(basket_arrays) == branchid_num_baskets[branch.cache_key]:
                arrays[branch.cache_key] = interpretation.final_array(
                    basket_arrays,
                    entry_start,
                    entry_stop,
                    branch.entry_offsets,
                    library,
                    branch,
                )
                # no longer needed, save memory
                basket_arrays.clear()

        except Exception:
            notifications.put(sys.exc_info())
        else:
            notifications.put(None)

    while len(arrays) < len(branchid_interpretation):
        obj = notifications.get()

        if isinstance(obj, uproot.source.chunk.Chunk):
            args = range_args[(obj.start, obj.stop)]
            decompression_executor.submit(chunk_to_basket, obj, *args)

        elif isinstance(obj, uproot.models.TBasket.Model_TBasket):
            interpretation_executor.submit(basket_to_array, obj)

        elif obj is None:
            pass

        elif isinstance(obj, tuple) and len(obj) == 3:
            uproot.source.futures.delayed_raise(*obj)

        else:
            raise AssertionError(obj)

        obj = None  # release before blocking


def _fix_asgrouped(arrays, expression_context, branchid_interpretation, library, how):
    index_start = 0
    for index_stop, (_, context) in enumerate(expression_context):
        if context["is_branch"]:
            branch = context["branches"][-1]
            interpretation = branchid_interpretation[branch.cache_key]
            if isinstance(interpretation, uproot.interpretation.grouped.AsGrouped):
                assert arrays[branch.cache_key] is None

                limited_context = dict(expression_context[index_start:index_stop])

                subarrays = {}
                subcontext = []
                for subname in interpretation.subbranches:
                    subbranch = branch[subname]
                    subarrays[subname] = arrays[subbranch.cache_key]
                    subcontext.append((subname, limited_context[subname]))

                arrays[branch.cache_key] = library.group(subarrays, subcontext, how)

                index_start = index_stop


def _hasbranches_num_entries_for(
    hasbranches, target_num_bytes, entry_start, entry_stop, branchid_interpretation
):
    total_bytes = 0.0
    for branch in hasbranches.itervalues(recursive=True):
        if branch.cache_key in branchid_interpretation:
            entry_offsets = branch.entry_offsets
            start = entry_offsets[0]
            for basket_num, stop in enumerate(entry_offsets[1:]):
                if entry_start < stop and start <= entry_stop:
                    total_bytes += branch.basket_compressed_bytes(basket_num)
                start = stop

    total_entries = entry_stop - entry_start
    if total_bytes == 0:
        num_entries = 0
    else:
        num_entries = int(round(target_num_bytes * total_entries / total_bytes))
    if num_entries <= 0:
        return 1
    else:
        return num_entries


def _regularize_step_size(
    hasbranches, step_size, entry_start, entry_stop, branchid_interpretation
):
    if uproot._util.isint(step_size):
        return step_size
    target_num_bytes = uproot._util.memory_size(
        step_size,
        "number of entries or memory size string with units "
        "(such as '100 MB') required, not {}".format(repr(step_size)),
    )
    return _hasbranches_num_entries_for(
        hasbranches, target_num_bytes, entry_start, entry_stop, branchid_interpretation
    )


def _get_dask_array(
    files,
    filter_name=no_filter,
    filter_typename=no_filter,
    filter_branch=no_filter,
    recursive=True,
    full_paths=False,
    step_size="100 MB",
    custom_classes=None,
    allow_missing=False,
    real_options=None,  # NOTE: a comma after **options breaks Python 2
):
    dask, da = uproot.extras.dask()
    hasbranches = []
    common_keys = None
    is_self = []

    count = 0
    for file_path, object_path in files:
        obj = uproot._util.regularize_object_path(
            file_path, object_path, custom_classes, allow_missing, real_options
        )

        if obj is not None:
            count += 1

            if isinstance(obj, TBranch) and len(obj.keys(recursive=True)) == 0:
                original = obj
                obj = obj.parent
                is_self.append(True)

                def real_filter_branch(branch):
                    return branch is original and filter_branch(branch)  # noqa: B023

            else:
                is_self.append(False)
                real_filter_branch = filter_branch

            hasbranches.append(obj)

            new_keys = obj.keys(
                recursive=recursive,
                filter_name=filter_name,
                filter_typename=filter_typename,
                filter_branch=real_filter_branch,
                full_paths=full_paths,
            )

            if common_keys is None:
                common_keys = new_keys
            else:
                new_keys = set(new_keys)
                common_keys = [key for key in common_keys if key in new_keys]

    if count == 0:
        raise ValueError(
            "allow_missing=True and no TTrees found in\n\n    {}".format(
                "\n    ".join(
                    "{"
                    + "{}: {}".format(
                        repr(f.file_path if isinstance(f, HasBranches) else f),
                        repr(f.object_path if isinstance(f, HasBranches) else o),
                    )
                    + "}"
                    for f, o in files
                )
            )
        )

    if len(common_keys) == 0 or not (all(is_self) or not any(is_self)):
        raise ValueError(
            "TTrees in\n\n    {}\n\nhave no TBranches in common".format(
                "\n    ".join(
                    "{"
                    + "{}: {}".format(
                        repr(f.file_path if isinstance(f, HasBranches) else f),
                        repr(f.object_path if isinstance(f, HasBranches) else o),
                    )
                    + "}"
                    for f, o in files
                )
            )
        )

    dask_dict = {}

    @dask.delayed
    def delayed_get_array(ttree, key, start, stop):
        return ttree[key].array(library="np", entry_start=start, entry_stop=stop)

    for key in common_keys:
        dask_arrays = []
        for ttree in hasbranches:
            entry_start, entry_stop = _regularize_entries_start_stop(
                ttree.tree.num_entries, None, None
            )
            entry_step = 0
            if uproot._util.isint(step_size):
                entry_step = step_size
            else:
                entry_step = ttree.num_entries_for(step_size, expressions=f"{key}")

            dt = ttree[key].interpretation.numpy_dtype
            if dt.subdtype is None:
                inner_shape = ()
            else:
                dt, inner_shape = dt.subdtype

            def foreach(start):
                stop = min(start + entry_step, entry_stop)  # noqa: B023
                length = stop - start

                delayed_array = delayed_get_array(ttree, key, start, stop)  # noqa: B023
                shape = (length,) + inner_shape  # noqa: B023
                dask_arrays.append(  # noqa: B023
                    da.from_delayed(delayed_array, shape=shape, dtype=dt)  # noqa: B023
                )

            for start in range(entry_start, entry_stop, entry_step):
                foreach(start)

        dask_dict[key] = da.concatenate(dask_arrays)
    return dask_dict


def _get_dask_array_delay_open(
    files,
    filter_name=no_filter,
    filter_typename=no_filter,
    filter_branch=no_filter,
    recursive=True,
    full_paths=False,
    custom_classes=None,
    allow_missing=False,
    real_options=None,  # NOTE: a comma after **options breaks Python 2
):
    dask, da = uproot.extras.dask()
    ffile_path, fobject_path = files[0]
    obj = uproot._util.regularize_object_path(
        ffile_path, fobject_path, custom_classes, allow_missing, real_options
    )
    common_keys = obj.keys(
        recursive=recursive,
        filter_name=filter_name,
        filter_typename=filter_typename,
        filter_branch=filter_branch,
        full_paths=full_paths,
    )

    dask_dict = {}
    delayed_open_fn = dask.delayed(uproot._util.regularize_object_path)

    @dask.delayed
    def delayed_get_array(ttree, key):
        return ttree[key].array(library="np")

    for key in common_keys:
        dask_arrays = []
        for file_path, object_path in files:
            delayed_tree = delayed_open_fn(
                file_path, object_path, custom_classes, allow_missing, real_options
            )
            delayed_array = delayed_get_array(delayed_tree, key)
            dt = obj[key].interpretation.numpy_dtype
            if dt.subdtype is not None:
                dt, inner_shape = dt.subdtype

            dask_arrays.append(
                da.from_delayed(delayed_array, shape=(numpy.nan,), dtype=dt)
            )
        dask_dict[key] = da.concatenate(dask_arrays, allow_unknown_chunksizes=True)
    return dask_dict


class _WrapDict(MutableMapping):
    def __init__(self, dict):
        self.dict = dict

    def __str__(self):
        return str(self.dict)

    def __repr__(self):
        return repr(self.dict)

    def __getitem__(self, where):
        return self.dict[where]

    def __setitem__(self, where, what):
        self.dict[where] = what

    def __delitem__(self, where):
        del self.dict[where]

    def __iter__(self, where):
        yield from self.dict

    def __len__(self):
        return len(self.dict)
