Flags.java

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package jdk.nashorn.internal.ir;

/**
 * Interface implemented by all nodes that have flags in
 * a lexical context. This is needed as we sometimes have to save
 * the setting of flags in the lexical context until a block
 * is completely finished and its final version (after multiple
 * copy on writes) is placed in the lexical context
 *
 * @param <T> lexical context node that can have flags set during code generation
 */
public interface Flags<T extends LexicalContextNode> {

    /**
     * Get all flags of a LexicalContextNode
     * @return flags
     */
    public int getFlags();

    /**
     * Check if a flag is set in a lexical context node
     * @param flag flag to check
     * @return flags
     */
    public boolean getFlag(int flag);

    /**
     * Clear a flag of a LexicalContextNode
     * @param lc lexical context
     * @param flag flag to clear
     * @return the new LexicalContext node if flags were changed, same otherwise
     */
    public T clearFlag(final LexicalContext lc, int flag);

    /**
     * Set a flag of a LexicalContextNode
     * @param lc lexical context
     * @param flag flag to set
     * @return the new LexicalContext node if flags were changed, same otherwise
     */
    public T setFlag(final LexicalContext lc, int flag);

    /**
     * Set all flags of a LexicalContextNode, overwriting previous flags
     * @param lc lexical context
     * @param flags new flags value
     * @return the new LexicalContext node if flags were changed, same otherwise
     */
    public T setFlags(final LexicalContext lc, int flags);
}