/*
 * Copyright (c) 2017, 2022, Oracle and/or its affiliates.
 * Copyright (c) 2013, Regents of the University of California
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are
 * permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this list of
 * conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other materials provided
 * with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.oracle.graal.python.nodes.frame;

import com.oracle.truffle.api.strings.TruffleString;

public abstract class FrameSlotIDs {
    private static final class ReturnSlotID {
        @Override
        public String toString() {
            return "<return_val>";
        }
    }

    public static final Object RETURN_SLOT_ID = new ReturnSlotID();

    private static final class TempLocalID {
        private final int index;

        public TempLocalID(int index) {
            this.index = index;
        }

        @Override
        public String toString() {
            return "<>temp" + index;
        }
    }

    public static final Object getTempLocal(int index) {
        return new TempLocalID(index);
    }

    /**
     * Used when body of class has two variables with the same name __class__. The first one is
     * __class__ freevar coming from outer scope and the second one is __class__ (implicit) closure
     * for inner methods, where __class__ or super is used. Both of them can have different values.
     */
    public static final Object FREEVAR__CLASS__ = new Object() {
        @Override
        public String toString() {
            return "<>freevar__class__";
        }
    };

    public static boolean isUserFrameSlot(Object key) {
        return key instanceof TruffleString;
    }
}
