construct(const TemplateBuilder& builder, const typename Model::Element& el, const SmartPtr<MathMLBinContainerElement>& elem) { elem->setChild(builder.getMathMLElement(el)); }
construct(const TemplateBuilder&, const typename Model::Element&, const SmartPtr<MathMLElement>&) { }
    construct(const TemplateBuilder& builder, const typename Model::Element& el, const SmartPtr<MathMLBinContainerElement>& elem)    { elem->setChild(builder.getMathMLElement(el)); }