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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
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 * 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 com.oracle.truffle.api.instrument;

/**
 * Program element "tags", presumed to be singletons (best implemented as enums) that define
 * user-visible behavior for debugging and other simple tools. These categories should correspond to
 * program structures, for example "statement" and "assignment", that are meaningful
 * ("human-sensible") to guest language programmers.
 * <p>
 * An untagged Truffle node should be understood as an artifact of the guest language implementation
 * and should not be visible to guest language programmers. Nodes may also have more than one tag,
 * for example a variable assignment that is also a statement. Finally, the assignment of tags to
 * nodes could depending on the use-case of whatever tool is using them.
 *
 * @see Probe
 * @see StandardSyntaxTag
 */
public interface SyntaxTag {

    /**
     * Human-friendly name of guest language program elements belonging to the category, e.g.
     * "statement".
     */
    String name();

    /**
     * Criteria and example uses for the tag.
     */
    String getDescription();

}