#
# This file is part of pySMT.
#
#   Copyright 2014 <NAME> and <NAME>
#
#   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
#   limitations under the License.
#

class Interpolator(object):

    def __init__(self):
        self._destroyed = False

    def binary_interpolant(self, a, b):
        """Returns a binary interpolant for the pair (a, b), if And(a, b) is
        unsatisfaiable, or None if And(a, b) is satisfiable.

        """
        raise NotImplementedError

    def sequence_interpolant(self, formulas):
        """Returns a sequence interpolant for the conjunction of formulas, or
        None if the problem is satisfiable.

        """
        raise NotImplementedError

    def __enter__(self):
        """Manage entering a Context (i.e., with statement)"""
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        """Manage exiting from Context (i.e., with statement)

        The default behaviour is to explicitely destroy the interpolator to
        free the associated resources.

        """
        self.exit()

    def exit(self):
        """Destroys the solver and closes associated resources."""
        if not self._destroyed:
            self._exit()
            self._destroyed = True

    def _exit(self):
        """Destroys the solver and closes associated resources."""
        raise NotImplementedError

#
# This file is part of pySMT.
#
#   Copyright 2014 <NAME> and <NAME>
#
#   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
#   limitations under the License.
#

class Interpolator(object):

    def __init__(self):
        self._destroyed = False

    def binary_interpolant(self, a, b):
        """Returns a binary interpolant for the pair (a, b), if And(a, b) is
        unsatisfaiable, or None if And(a, b) is satisfiable.

        """
        raise NotImplementedError

    def sequence_interpolant(self, formulas):
        """Returns a sequence interpolant for the conjunction of formulas, or
        None if the problem is satisfiable.

        """
        raise NotImplementedError

    def __enter__(self):
        """Manage entering a Context (i.e., with statement)"""
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        """Manage exiting from Context (i.e., with statement)

        The default behaviour is to explicitely destroy the interpolator to
        free the associated resources.

        """
        self.exit()

    def exit(self):
        """Destroys the solver and closes associated resources."""
        if not self._destroyed:
            self._exit()
            self._destroyed = True

    def _exit(self):
        """Destroys the solver and closes associated resources."""
        raise NotImplementedError

# # This file is part of pySMT. # #   Copyright 2014 <NAME> and <NAME> # #   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 #   limitations under the License. # Returns a binary interpolant for the pair (a, b), if And(a, b) is         unsatisfaiable, or None if And(a, b) is satisfiable. Returns a sequence interpolant for the conjunction of formulas, or         None if the problem is satisfiable. Manage entering a Context (i.e., with statement) Manage exiting from Context (i.e., with statement)          The default behaviour is to explicitely destroy the interpolator to         free the associated resources. Destroys the solver and closes associated resources. Destroys the solver and closes associated resources.