/*
 * The Apache Software License, Version 1.1
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 * reserved.
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 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation and was
 * originally based on software copyright (c) 2002, International
 * Business Machines Corporation., http://www.ibm.com.  For more
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 */
package org.apache.xpath.expression;

/**
 * Represents <em>path</em> expressions. <quote>It can be used to locate nodes within a tree.</quote>
 * <p>A path expression consists of a sequence of {@link StepExpr}. 
 * It's a {@link OperatorExpr operator-based} expression
 * with {@link OperatorExpr#SLASH_STEP} as the operator separator 
 * and {@link Expr#PATH_EXPR} as the operator type. 
 * </p> 
 * <p>"//" is always expanded as /descendant-or-self::node()/.</p>
 * <p>In the same manner, the initial / is expanded as fn:root(self::node()).
 * The convenient {@link #isAbsolute()} method may be used to test whether
 * or not the path expression is absolute.</p>
 * @see <a href="http://www.w3.org/TR/xpath20/#id-path-expression">
 * XPath 2.0 specification</a>
 */
public interface PathExpr extends OperatorExpr {

    /**
     * Test whether the path is absolute or not
     * @return boolean true whether absolute
     */
    boolean isAbsolute();
}