# Source code for ufl_legacy.exprcontainers

    # -*- coding: utf-8 -*-
    """This module defines special types for representing mapping of expressions to expressions."""

    # Copyright (C) 2014 Martin Sandve Alnæs
    #
    # This file is part of UFL (https://www.fenicsproject.org)
    #
    # SPDX-License-Identifier:    LGPL-3.0-or-later

    from ufl_legacy.log import error
    from ufl_legacy.core.expr import Expr
    from ufl_legacy.core.operator import Operator
    from ufl_legacy.core.ufl_type import ufl_type

    # --- Non-tensor types ---

    @ufl_type(num_ops="varying")
    class ExprList(Operator):
        "List of Expr objects. For internal use, never to be created by end users."
        __slots__ = ()

        def __init__(self, *operands):
            Operator.__init__(self, operands)
            if not all(isinstance(i, Expr) for i in operands):
                error("Expecting Expr in ExprList.")

        def __getitem__(self, i):
            return self.ufl_operands[i]

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

        def __iter__(self):
            return iter(self.ufl_operands)

        def __str__(self):
            return "ExprList(*(%s,))" % ", ".join(str(i) for i in self.ufl_operands)

        def __repr__(self):
            r = "ExprList(*%s)" % repr(self.ufl_operands)
            return r

        @property
        def ufl_shape(self):
            error("A non-tensor type has no ufl_shape.")

        @property
        def ufl_free_indices(self):
            error("A non-tensor type has no ufl_free_indices.")

        def free_indices(self):
            error("A non-tensor type has no free_indices.")

        @property
        def ufl_index_dimensions(self):
            error("A non-tensor type has no ufl_index_dimensions.")

        def index_dimensions(self):
            error("A non-tensor type has no index_dimensions.")

    @ufl_type(num_ops="varying")
    class ExprMapping(Operator):
        "Mapping of Expr objects. For internal use, never to be created by end users."
        __slots__ = ()

        def __init__(self, *operands):
            Operator.__init__(self, operands)
            if not all(isinstance(e, Expr) for e in operands):
                error("Expecting Expr in ExprMapping.")

        def ufl_domains(self):
            # Because this type can act like a terminal if it has no
            # operands, we need to override some recursive operations
            if self.ufl_operands:
                return Operator.ufl_domains()
            else:
                return []

        # def __getitem__(self, key):
        #     return self.ufl_operands[key]

        # def __len__(self):
        #     return len(self.ufl_operands) // 2

        # def __iter__(self):
        #     return iter(self.ufl_operands[::2])

        def __str__(self):
            return "ExprMapping(*%s)" % repr(self.ufl_operands)

        def __repr__(self):
            r = "ExprMapping(*%s)" % repr(self.ufl_operands)
            return r

        @property
        def ufl_shape(self):
            error("A non-tensor type has no ufl_shape.")

        @property
        def ufl_free_indices(self):
            error("A non-tensor type has no ufl_free_indices.")

        def free_indices(self):
            error("A non-tensor type has no free_indices.")

        @property
        def ufl_index_dimensions(self):
            error("A non-tensor type has no ufl_index_dimensions.")

        def index_dimensions(self):
            error("A non-tensor type has no index_dimensions.")