RepeatingNode.java

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 * accompanied this code).
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package com.oracle.truffle.api.nodes;

import com.oracle.truffle.api.TruffleRuntime;
import com.oracle.truffle.api.frame.VirtualFrame;

/**
 * A node that is repeatedly invoked as part of a Truffle loop control structure. Repeating nodes
 * must extend {@link Node} or a subclass of {@link Node}.
 *
 * Repeating nodes are intended to be implemented by guest language implementations. For a full
 * usage example please see {@link LoopNode}.
 *
 * @see LoopNode
 * @see TruffleRuntime#createLoopNode(RepeatingNode)
 * @since 0.8 or earlier
 */
public interface RepeatingNode extends NodeInterface {

    /**
     * Repeatedly invoked by a {@link LoopNode loop node} implementation until the method returns
     * <code>false</code> or throws an exception.
     *
     * @param frame the current execution frame passed through the interpreter
     * @return <code>true</code> if the method should be executed again to complete the loop and
     *         <code>false</code> if it must not.
     * @since 0.8 or earlier
     */
    boolean executeRepeating(VirtualFrame frame);

}