Source code for compas_fab.utilities.lazy_loader


# Code from https://github.com/tensorflow/tensorflow/blob/master/tensorflow/python/util/lazy_loader.py
# Copyright 2015 The TensorFlow Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
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# ==============================================================================
"""A LazyLoader class."""

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import importlib
import types


[docs]class LazyLoader(types.ModuleType): """Lazily import a module, mainly to avoid pulling in large dependencies. `contrib`, and `ffmpeg` are examples of modules that are large and not always needed, and this allows them to only be loaded when they are used. """ # The lint error here is incorrect.
[docs] def __init__(self, local_name, parent_module_globals, name): # pylint: disable=super-on-old-class self._local_name = local_name self._parent_module_globals = parent_module_globals super(LazyLoader, self).__init__(name)
def _load(self): # Import the target module and insert it into the parent's namespace module = importlib.import_module(self.__name__) self._parent_module_globals[self._local_name] = module # Update this object's dict so that if someone keeps a reference to the # LazyLoader, lookups are efficient (__getattr__ is only called on lookups # that fail). self.__dict__.update(module.__dict__) return module def __getattr__(self, item): module = self._load() return getattr(module, item) def __dir__(self): module = self._load() return dir(module)