src/main/java/org/apache/sling/scripting/sightly/impl/compiler/Patterns.java

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 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
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 *
 *   http://www.apache.org/licenses/LICENSE-2.0
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 * Unless required by applicable law or agreed to in writing,
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package org.apache.sling.scripting.sightly.impl.compiler;

import org.apache.sling.scripting.sightly.compiler.commands.Conditional;
import org.apache.sling.scripting.sightly.compiler.commands.VariableBinding;
import org.apache.sling.scripting.sightly.compiler.expression.nodes.BooleanConstant;

/**
 * The {@code Patterns} class provides various static methods that implement commonly used stream processing commands.
 */
public final class Patterns {

    private static final String ALWAYS_FALSE_VAR = "always_false";

    /**
     * Inserts a sequence of commands that will ignore the rest of the stream until
     * the end stream sequence is inserted
     * @param stream - the stream
     */
    public static void beginStreamIgnore(PushStream stream) {
        stream.write(new VariableBinding.Start(ALWAYS_FALSE_VAR, BooleanConstant.FALSE));
        stream.write(new Conditional.Start(ALWAYS_FALSE_VAR, true));
    }

    /**
     * Inserts a sequence of commands that cancels stream ignore
     * @param stream - the input stream
     */
    public static void endStreamIgnore(PushStream stream) {
        stream.write(Conditional.END);
        stream.write(VariableBinding.END);
    }


}