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#ifndef txXPathOptimizer_h__
#define txXPathOptimizer_h__

#include "txCore.h"

class Expr;

class txXPathOptimizer
{
public:
    /**
     * Optimize the given expression.
     * @param aInExpr       Expression to optimize.
     * @param aOutExpr      Resulting expression, null if optimization didn't
     *                      result in a new expression.
     */
    nsresult optimize(Expr* aInExpr, Expr** aOutExpr);

private:
    // Helper methods for optimizing specific classes
    nsresult optimizeStep(Expr* aInExpr, Expr** aOutExpr);
    nsresult optimizePath(Expr* aInExpr, Expr** aOutExpr);
    nsresult optimizeUnion(Expr* aInExpr, Expr** aOutExpr);
};

#endif