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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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package org.openjdk.btrace.instr.templates;

/**
 * An interface to be implemented by the template expanders
 *
 * @author Jaroslav Bachorik
 * @since 1.3
 */
public interface TemplateExpander {
  /**
   * The expander identifies and, possibly, expands the given template
   *
   * @param v The expander parent
   * @param t The template to process
   * @return appropriate {@linkplain Result} value
   */
  Result expand(TemplateExpanderVisitor v, Template t);

  /** Called upon code points invalidating the current expander status */
  void resetState();

  /**
   * The result of expansion
   *
   * <ul>
   *   <li><b>EXPANDED</b> = expander has claimed and expanded the template
   *   <li><b>CLAIMED</b> = expander has claimed the template but didn't expand it
   *   <li><b>IGNORED</b> = expander has not claimed the template
   * </ul>
   */
  enum Result {
    EXPANDED,
    CLAIMED,
    IGNORED
  }

  /** A knockoff of the java.util.function.Consumer interface for pre-8 usage */
  interface Consumer<T> {
    void consume(T visitor);
  }
}
