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src/sql/resolver/expr/ob_raw_expr_canonicalizer.h

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+/**
+ * Copyright (c) 2021 OceanBase
+ * OceanBase CE is licensed under Mulan PubL v2.
+ * You can use this software according to the terms and conditions of the Mulan PubL v2.
+ * You may obtain a copy of Mulan PubL v2 at:
+ *          http://license.coscl.org.cn/MulanPubL-2.0
+ * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+ * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ * See the Mulan PubL v2 for more details.
+ */
+
+#ifndef _OB_RAW_EXPR_CANONICALIZER_H
+#define _OB_RAW_EXPR_CANONICALIZER_H 1
+#include "sql/resolver/expr/ob_raw_expr.h"
+namespace oceanbase {
+namespace sql {
+class ObRawExprCanonicalizer {
+  public:
+  ObRawExprCanonicalizer()
+  {}
+  virtual ~ObRawExprCanonicalizer()
+  {}
+  /**
+   * Canonicalize the expression.
+   *
+   * @param expr [in/out]
+   *
+   * @return error code
+   */
+  virtual int canonicalize(ObRawExpr*& expr) = 0;
+
+  private:
+  // types and constants
+  private:
+  // disallow copy
+  DISALLOW_COPY_AND_ASSIGN(ObRawExprCanonicalizer);
+  // function members
+  private:
+  // data members
+};
+
+}  // end namespace sql
+}  // end namespace oceanbase
+
+#endif /* _OB_RAW_EXPR_CANONICALIZER_H */