public static AbstractState factory(string backend, string fluid_names)
 {
     if (Environment.Is64BitProcess)
     {
         IntPtr        cPtr = CoolPropPINVOKE64.AbstractState_factory__SWIG_0(backend, fluid_names);
         AbstractState ret  = (cPtr == IntPtr.Zero) ? null : new AbstractState(cPtr, false);
         //if (CoolPropPINVOKE64.SWIGPendingException.Pending) throw CoolPropPINVOKE64.SWIGPendingException.Retrieve();
         return(ret);
     }
     else
     {
         IntPtr        cPtr = CoolPropPINVOKE.AbstractState_factory__SWIG_0(backend, fluid_names);
         AbstractState ret  = (cPtr == IntPtr.Zero) ? null : new AbstractState(cPtr, false);
         //if (CoolPropPINVOKE.SWIGPendingException.Pending) throw CoolPropPINVOKE.SWIGPendingException.Retrieve();
         return(ret);
     }
 }