/*
 * Copyright (C) 2023 Apple Inc. 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 APPLE INC. AND ITS 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 APPLE INC. OR ITS 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
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#include "ASTExpression.h"

namespace WGSL::AST {

// This is a special node used when modifying the AST through compiler passes.
// The passes can replace one node with another, but only if the size of the new
// class fits in the existing space. This is a small node used when needing to insert a
// larger node than the one current in the tree. E.g. replacing an identifier
// with a structure access.
class IdentityExpression final : public Expression {
    WGSL_AST_BUILDER_NODE(IdentityExpression);
public:
    NodeKind kind() const override;
    Expression& expression() { return m_expression.get(); }

private:
    IdentityExpression(SourceSpan span, Expression::Ref&& expression)
        : Expression(span)
        , m_expression(WTFMove(expression))
    {
        m_inferredType = m_expression.get().inferredType();
    }

    Expression::Ref m_expression;
};

} // namespace WGSL::AST

SPECIALIZE_TYPE_TRAITS_WGSL_AST(IdentityExpression)