Re: Passing array by reference

Carl Barron <>
Wed, 18 Jul 2007 20:35:06 CST
In article <XVqni.57$>, john
<> wrote:


quick question - got a function like:

void CalculateApproach(float (&Params)[4], double (&ObjectPos)[3],
double (&VehiclePos)[4], double (&NewPos)[4])

OK, the seconds argument should come from an array but this array is
bigger than the expected 3 i.e it has 10 elements but I only need 4,5
and 6 so I tried something like:

CalculateApproach(fAppParams, &dFeatures[4], dCurVehPos, dNewVehPos);

but it fails for me. Am I trying to do something that is not allowed and
hence should just make new array[3] and copy my values in and then pass
it into the function or can someone give me hint towards the syntax i
should be using if it can work?

  typedef double DoubleFour[4];
  typedef double DoubleThree[3];

   void CalculateApproach(DoubleFour &,DoubleThree &,DoubleFour
&,DoubleFor &);

    CalculateApproach(fAppParams, (DoubleThree &)(dFeatures[4]),

 this should work, as an array must be decayable to a pointer so the
cast is only to tell the compiler what is going on. A reinterpret_cast
will be needed and this is a strong warning that it might not be

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