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Re: Const structure pointer as template argument



typedef struct testStruct
{
    long a;
} testStruct;

template <const testStruct * bob> class Helper
{
};

// this compiles
testStruct nonConstTestStruct = {0};
Helper<&nonConstTestStruct> HelperNonConst;

// this doesn't
const testStruct constTestStruct = {0};
Helper<&constTestStruct> HelperConst;

Unless you're trying to do something very subtle, I reckon that this is
really what you wanted to do:

   struct testStruct
   {
       long a;
   };

   template <class T> class Helper
   {
   };

   testStruct nonConstTestStruct = {0};
   Helper<testStruct*> HelperNonConst;

   const testStruct constTestStruct = {0};
   Helper<const testStruct*> HelperConst;


If you had a need to pass a const or non-const pointer into the Helper
so that it references a testStruct, then change the definition to this:

   template <class T> class Helper
   {
       Helper(T object) : myObject(object) {};
       T   myObject;
   };

   const testStruct constTestStruct = {0};
   Helper<const testStruct*> HelperConst(&constTestStruct);

Paul


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References: 
 >Const structure pointer as template argument (From: Ladd Van Tol <email@hidden>)



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