# Copyright 2023 The Boax Authors.
#
# 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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"""Base interface for optimizers."""

from typing import Protocol, Tuple

from boax.utils.typing import Array, PRNGKey


class Optimizer(Protocol):
  """
  A callable type for the optimization functions.
  """

  def __call__(self, key: PRNGKey) -> Tuple[Array, Array]:
    """
    The optimization function.

    Args:
      key: A PRNG key.

    Returns:
      A tuple of the maxima and their acquisition values.
    """
