hi all

I am trying to use mpl to do some simple type computation that involves nest if statements

The logic is somewhat like

if(T is Libor)

    return LiborType

if(

   or(

      or(T = Euribor,

         T = EURLibor),

      is_base_of(T, Libor)

    ),

    ConstrType2,

    if( 

        or(is_base_of(T, Euribor),

           is_base_of(T, EURLibor)),

       ConstrType1,

       ConstrType

      )

   )
When I first coded it and instantiate T with some derived class of Libor, the final type is always a generic type. Few more testing shows that the inner if_ in the code below
   typedef typename

      boost::mpl::if_

      <

          boost::is_same<InType, QuantLib::Libor>,

          QuantLib::Libor,

          boost::mpl::if_

          <

                  boost::mpl::or_

                  <

                      boost::is_same<InType, QuantLib::Euribor>,

                      boost::is_same<InType, QuantLib::EURLibor>,

                      boost::is_base_of<QuantLib::Libor, InType>

                  >

              ConstrType2,

              boost::mpl::if_

              <

                  boost::mpl::or_

                  <

                      boost::is_base_of<QuantLib::Euribor, InType>,

                      boost::is_base_of<QuantLib::EURLibor, InType>

                  >,

                  ConstrType1,

                  ConstrType

              > 

          > 

      >::type Type;





does not reduce to ConstrType1/ConstrType2/ConstrType but the whole is used as a type. So the final Type is just a type with 3 nested if_ class inside. I tried linearising the logic but this introduces other problem. Is this a bug or a limitation of mpl::if_?



Thanks